CN207588821U - A kind of anti-interference low-pass filter - Google Patents
A kind of anti-interference low-pass filter Download PDFInfo
- Publication number
- CN207588821U CN207588821U CN201721504456.7U CN201721504456U CN207588821U CN 207588821 U CN207588821 U CN 207588821U CN 201721504456 U CN201721504456 U CN 201721504456U CN 207588821 U CN207588821 U CN 207588821U
- Authority
- CN
- China
- Prior art keywords
- capacitance
- resistance
- inductance
- connect
- pass filter
- 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.)
- Expired - Fee Related
Links
Landscapes
- Filters And Equalizers (AREA)
- Networks Using Active Elements (AREA)
Abstract
The utility model discloses a kind of anti-interference low-pass filters, mainly solve the problem of that poor anti jamming capability radio frequency output in the prior art is unstable.The low-pass filter includes the input port Port1 for the input of external radio frequency, the filter circuit being connect with input port Port1, the balancing circuitry being connect with filter circuit and the output port Port2 for connecting with balancing circuitry, being exported for radio frequency.Wherein, filter circuit uses the T-type structure of three ranks, increases filtering zero, improves rejection ability.In addition, adding the balancing circuitry with feedback, make radio frequency output more stable.Through the above scheme, the utility model has many advantages, such as that of simple structure and low cost, output is stable, strong antijamming capability, has very high practical value and promotional value in technical field of filtering.
Description
Technical field
The utility model is related to technical field of filtering, especially a kind of anti-interference low-pass filter.
Background technology
Wave filter is the filter circuit formed using the combination of inductance, capacitance and resistance, because inductance coil have logical low frequency,
High frequency characteristics is hindered, certain primary or multiple harmonic can be filtered out, has the function of to filter out noise and separation signal, be widely used in electricity
Sub- equipment transmission field.Wherein, LC wave filters can be divided into according to function：LC low-pass filters, LC bandpass filters, high-pass filtering
Device, LC all-pass filters and LC bandstop filters.At present, traditional low-pass filter uses linear structure design method, no
Foot part is that the Out-of-band rejection of the wave filter of design is than relatively low, to deviateing other than the limited occupancy band limits of assigned frequency
Signal rejection ability is poor, and a part of interference signal is certainly existed in circuit, causes filter effect poor, wave filter antijamming capability
Difference.In addition, the waveform of filtering output has disturbance, the function of stablizing output can not be realized.
Therefore, it is necessary to be improved to low-pass filter, to obtain strong antijamming capability, radio frequency input is stablized, with outer suppression
The strong low-pass filtering of ability processed.
Utility model content
Against the above deficiency, the purpose of this utility model is to provide a kind of anti-interference low-pass filters, mainly solve existing
There is the problem of poor anti jamming capability present in technology, radio frequency output is unstable.
To achieve these goals, the technical solution adopted in the utility model is as follows：
A kind of anti-interference low-pass filter, the input port Port1 including being used for external radio frequency input, with input port
The filter circuit of Port1 connections, the balancing circuitry being connect with filter circuit and connect with balancing circuitry, for radio frequency export
Output port Port2.
Specifically, the filter circuit include latter termination input port Port1 in parallel and the resistance R1 of other end ground connection,
Capacitance C1 and inductance L1, the capacitance C2 that one end is connect with input port Port1, it is in parallel after one end connect with the capacitance C2 other ends and
Resistance R2, capacitance C3 and the inductance L2 of other end ground connection, the capacitance C4 and series connection that one end is connect with the capacitance C2 other ends are latter
End is connect with the capacitance C4 other ends and the resistance R3 and inductance L3 of other end ground connection.
Further, the balancing circuitry includes the power amplifier that input cathode is connect with the capacitance C4 other ends, one end
The resistance R4 of connection and other end ground connection, one end and power amplifier output connection and another termination work(are exported with power amplifier
The termination power amplification input anodes of resistance R5 and one of rate amplification input anode and the resistance R6 of other end ground connection.By setting
The resistance R5 of output feedback is put, is compared with power amplification input, by the way of feedback, to obtain stable output.
Preferably, it is in parallel with capacitance C2 after the resistance R1, inductance L1, capacitance C1 parallel connections to form the first filtering T-type structure.
Further, it is in parallel with capacitance C4 after the resistance R2, inductance L2, capacitance C3 parallel connections to form the second filtering T junction
Structure.
Further, it is in parallel with capacitance C4 after the resistance R3 and inductance L3 series connection to form third filtering T-type structure.And
Connection resonance constitutes T-type structure, increases circuit zero, improves Out-of-band rejection ability, antijamming capability enhancing.
Preferably, the power amplifier is LM358.
Further, the resistance R1 is 11k Ω, and resistance R2 is 11k Ω, and resistance R3 is 7.4k Ω, and resistance R4 is 6.5k
Ω, resistance R45 are 6.5k Ω, and resistance R6 is 1k Ω, and capacitance C1 is 0.05uF, and capacitance C3 is 0.047uF, and capacitance C3 is
0.05uF, capacitance C4 are 0.0045uF, and inductance L1 is 0.71H, and inductance L2 is 0.71H, and inductance L3 is 0.94H.
Compared with prior art, the utility model has the advantages that：
The utility model cleverly sets the T-type structure that anti-interference, multiple harmonic filters out, with the zero of filter circuit.
Ensure the premise of the output of low-pass filtering, by adjusting dead-center position, be improved Out-of-band rejection, the antijamming capability of circuit
It is remarkably reinforced.In addition, adding the balancing circuitry that radio frequency stablizes the feedback of output after filter circuit, radio frequency output can effectively avoid
Wave phenomenon, the radiofrequency signal of output are more accurate.In conclusion the utility model has of simple structure and low cost, output
The advantages that stabilization, strong antijamming capability, has very high practical value and promotional value in technical field of filtering.
Description of the drawings
Fig. 1 is the schematic diagram of the utility model.
Specific embodiment
The utility model is described in further detail with reference to the accompanying drawings and examples, and the embodiment of the utility model includes
But it is not limited to the following example.
Embodiment
As shown in Figure 1, the utility model provides a kind of anti-interference low-pass filter, anti-interference and Out-of-band rejection energy is improved
Power makes radio frequency input more stable.The wave filter includes the input port Port1 for the input of external radio frequency, with input port
The filter circuit of Port1 connections, the balancing circuitry being connect with filter circuit and connect with balancing circuitry, for radio frequency export
Output port Port2.Wherein, filter circuit includes latter termination input port Port1 in parallel and the resistance of other end ground connection
R1, capacitance C1 and inductance L1, the capacitance C2 that one end is connect with input port Port1, one end connects with the capacitance C2 other ends after parallel connection
It connects and resistance R2, capacitance C3 and the inductance L2 of other end ground connection, capacitance C4 that one end is connect with the capacitance C2 other ends and connects
The resistance R3 and inductance L3 that one end is connect with the capacitance C4 other ends afterwards and the other end is grounded.Balancing circuitry includes input cathode and electricity
Hold the LM358 power amplifiers of C4 other ends connection, one end and power amplifier output connection and the resistance R4 of other end ground connection,
One end and power amplifier output connection and the termination power amplifications of resistance R5 and one of another termination power amplification input anode
Input anode and the resistance R6 of other end ground connection.By setting the resistance R5 of output feedback, it is compared with power amplification input,
By the way of feedback, to obtain stable output.It is in parallel with capacitance C2 after resistance R1, inductance L1, capacitance C1 parallel connections to form the
One filtering T-type structure.It is in parallel with capacitance C4 after resistance R2, inductance L2, capacitance C3 parallel connections to form the second filtering T-type structure.Resistance
It is in parallel with capacitance C4 after R3 and inductance L3 series connection to form third filtering T-type structure.Pass through the parallel connection that three-level T-type structure is set to filter
Resonance circuit, to obtain more circuit zeros, the zero number for increasing circuit is filtered, and improves antijamming capability, enhances band
Outer inhibition.
By taking third-order low-pass filter as an example, the resistance R1 of the wave filter is 11k Ω, and resistance R2 is 11k Ω, and resistance R3 is
7.4k Ω, resistance R4 are 6.5k Ω, and resistance R45 is 6.5k Ω, and resistance R6 is 1k Ω, and capacitance C1 is 0.05uF, and capacitance C3 is
0.047uF, capacitance C3 are 0.05uF, and capacitance C4 is 0.0045uF, and inductance L1 is 0.71H, and inductance L2 is 0.71H, and inductance L3 is
0.94H。
The utility model, to increase the zero of circuit, it is anti-interference to improve low-pass filter circuit by the filtering of three ranks of setting
At the same time ability, sets the balancing circuitry of feedback, makes radio frequency output signal more stable, reduce output bias.In conclusion
The utility model compared with prior art, has the characteristics that substantive and progress, is had a vast market in technical field of filtering
Prospect and promotional value.
Above-described embodiment is only the preferred embodiment of the utility model, is not intended to limit the scope of the present invention,
In every case the design principle of the utility model and the variation for carrying out non-creative labour on this basis and making are used, it should all
Belong within the scope of protection of the utility model.
Claims (6)
1. a kind of anti-interference low-pass filter, which is characterized in that the input port Port1 including being used for external radio frequency input, with
The filter circuit of input port Port1 connections, the balancing circuitry being connect with filter circuit and connect with balancing circuitry, is used for
The output port Port2 of radio frequency output；
The filter circuit includes latter termination input port Port1 in parallel and resistance R1, capacitance C1 and the electricity of other end ground connection
Feel L1, the capacitance C2 that one end is connect with input port Port1, one end is connect with the capacitance C2 other ends after parallel connection and the other end is grounded
Resistance R2, capacitance C3 and inductance L2, one end and capacitance C4 after capacitance C4 that one end is connect with the capacitance C2 other ends and series connection
The other end connects and the resistance R3 and inductance L3 of other end ground connection；
The balancing circuitry includes the power amplifier that input cathode is connect with the capacitance C4 other ends, and one end is defeated with power amplifier
Go out the resistance R4 of connection and other end ground connection, one end and power amplifier output connection and another termination power amplification input anode
Resistance R5 and one termination power amplification input anode and the other end ground connection resistance R6.
2. anti-interference low-pass filter according to claim 1, which is characterized in that the resistance R1, inductance L1, capacitance C1
It is in parallel with capacitance C2 after parallel connection to form the first filtering T-type structure.
3. anti-interference low-pass filter according to claim 1, which is characterized in that the resistance R2, inductance L2, capacitance C3
It is in parallel with capacitance C4 after parallel connection to form the second filtering T-type structure.
4. anti-interference low-pass filter according to claim 1, which is characterized in that after the resistance R3 and inductance L3 series connection
Composition third filtering T-type structure in parallel with capacitance C4.
5. according to the anti-interference low-pass filter of Claims 1 to 4 any one of them, which is characterized in that the power amplifier
For LM358.
6. anti-interference low-pass filter according to claim 5, which is characterized in that the resistance R1 is 11k Ω, resistance R2
For 11k Ω, resistance R3 is 7.4k Ω, and resistance R4 is 6.5k Ω, and resistance R45 is 6.5k Ω, and resistance R6 is 1k Ω, and capacitance C1 is
0.05uF, capacitance C3 are 0.047uF, and capacitance C3 is 0.05uF, and capacitance C4 is 0.0045uF, and inductance L1 is 0.71H, and inductance L2 is
0.71H, inductance L3 are 0.94H.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201721504456.7U CN207588821U (en) | 2017-11-13 | 2017-11-13 | A kind of anti-interference low-pass filter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201721504456.7U CN207588821U (en) | 2017-11-13 | 2017-11-13 | A kind of anti-interference low-pass filter |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN207588821U true CN207588821U (en) | 2018-07-06 |
Family
ID=62731421
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201721504456.7U Expired - Fee Related CN207588821U (en) | 2017-11-13 | 2017-11-13 | A kind of anti-interference low-pass filter |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN207588821U (en) |
-
2017
- 2017-11-13 CN CN201721504456.7U patent/CN207588821U/en not_active Expired - Fee Related
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| WO2019010858A1 (en) | Circuit structure and method for improving harmonic suppression capability of radio frequency power amplifier | |
| CN206041939U (en) | RF power amplifier output matching circuit structure | |
| CN206226382U (en) | Radio-frequency power amplifier and its output matching circuit | |
| CN207490871U (en) | A kind of multi-frequency band radio-frequency power amplifier | |
| CN207588821U (en) | A kind of anti-interference low-pass filter | |
| CN204119188U (en) | A kind of Novel Filter | |
| CN205961073U (en) | A double frequency -band band pass filter for laser rangefinder | |
| CN104967409B (en) | One kind being based on the novel Terahertz Design of frequency multiplier structure of high Low ESR | |
| CN204859132U (en) | Adopt 4580 to transport active low -pass filter circuit of putting | |
| CN102075154B (en) | Low-power consumption programmable gain amplifier device | |
| CN104333339A (en) | Adjustable transformer | |
| CN207039550U (en) | A kind of anti-interference low bit error wave filter | |
| CN107888163A (en) | A kind of anti-interference low pass filter | |
| CN204206123U (en) | A kind of chain type low-pass filter circuit | |
| CN204206126U (en) | A kind of adjustable transformer | |
| CN206865425U (en) | Fourth-order band-pass wave filter with gain amplifier | |
| CN105897205B (en) | A kind of variable gain instrument amplifier of low-pass filtering | |
| CN104202006A (en) | Adjustable simple low-pass filtering circuit | |
| CN108259021A (en) | A kind of CMOS broadbands distribution variable band-pass filter | |
| CN206117607U (en) | Active bandwidth -limited circuit of low frequency | |
| CN204119180U (en) | A kind of adjustable simple and easy low-pass filter circuit | |
| CN202178740U (en) | Low pass filter | |
| CN204304947U (en) | A kind of low-pass filter circuit | |
| CN109302163A (en) | A kind of modified Anti-aliasing Filter Circuits | |
| CN203984365U (en) | A kind of adjustable printed panel transformer |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20180706 Termination date: 20181113 |
|
| CF01 | Termination of patent right due to non-payment of annual fee |