CN111062184B - Quick three-pin automatic impedance matching system - Google Patents
Quick three-pin automatic impedance matching system Download PDFInfo
- Publication number
- CN111062184B CN111062184B CN201911267864.9A CN201911267864A CN111062184B CN 111062184 B CN111062184 B CN 111062184B CN 201911267864 A CN201911267864 A CN 201911267864A CN 111062184 B CN111062184 B CN 111062184B
- Authority
- CN
- China
- Prior art keywords
- pin
- equivalent
- impedance matching
- waveguide
- parameters
- 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.)
- Active
Links
Images
Landscapes
- Measurement Of Resistance Or Impedance (AREA)
Abstract
The invention relates to the technical field of three-pin automatic impedance matching, in particular to a rapid three-pin automatic impedance matching system. The rapid three-pin automatic impedance matching system comprises the following steps: 1) establishing a three-pin waveguide equivalent circuit; 2) establishing a circuit parameter relationship; 3) and (4) designing a matching algorithm. The invention directly establishes the mathematical relationship among the reflection coefficient, the load impedance, the pin depth and the S parameter of the three-pin waveguide, can quickly calculate the scattering parameter and the load impedance according to the reflection coefficient and the pin depth, and further realizes quick impedance matching calculation. Based on an equivalent circuit method and numerical calculation, the method can greatly reduce the operation amount, simplify the design process of automatic impedance matching, does not need a database, and can be widely used for pin waveguides with different sizes.
Description
Technical Field
The invention relates to the technical field of three-pin automatic impedance matching, in particular to a rapid three-pin automatic impedance matching system.
Background
In high power microwave industrial applications, in the order of many kilowatts, an impedance matching system is an essential component. The system itself is reflective due to the different characteristic impedances of the individual microwave devices in the system. The reflected energy causes low transmission efficiency and damage to the components. To eliminate reflections and maximize the power drawn by the load from the power source, we need to conjugate the equivalent waveguide impedance to the load impedance. The pin waveguide can adjust the scattering parameters of the waveguide in a mode of adjusting the depth of the pin, so that impedance matching is realized. The efficiency and accuracy of impedance matching is critical to the efficiency and stability of the overall system. However, since the characteristic impedance of the load is constantly changing, real-time, fast and stable automatic impedance matching is not easy to implement.
The traditional automatic impedance matching technology generally utilizes a finite element method simulation or experimental measurement mode to establish a database of the relationship between the pin depth and scattering parameters of two ports of a pin waveguide, measures the reflection coefficient of the cross section of a feed port of the three pin waveguide through a six-port device or a dual-directional coupler, calculates a terminal load corresponding to a terminating heating cavity according to the reflection coefficient by designing an impedance matching algorithm, then searches the established database to obtain the insertion depth of the three pins meeting the required standing-wave ratio, and finally sends an instruction to a PLC (programmable logic controller) to control a stepping motor to drive the pins to a specified position so as to complete impedance matching.
The traditional impedance matching system needs to repeatedly simulate or measure the parameters of the waveguide during design, especially needs to use a large amount of calculation when the matching efficiency and precision requirements are high, the design process is low in efficiency, a large amount of databases need to be built, the impedance matching system is only suitable for pin waveguides with the same size, and once the size of the waveguide is changed, the whole system needs to be redesigned.
Disclosure of Invention
In order to solve the problems in the prior art, the invention aims to provide a matching algorithm, which abandons the original method for establishing a database based on simulation and measurement, changes an equivalent circuit analysis method into the method for equating the waveguide part of the three-pin waveguide to be a cascaded transmission line, equates the pin part to be a capacitor, establishes the relation among the pin depth, the load impedance and the reflection coefficient through a transmission line theory, and finally selects a depth combination with the minimum reflection coefficient as a final solution by simulating the reflection coefficients under different loads and different pin depths.
In order to achieve the purpose, the technical scheme of the invention is as follows:
a fast three-pin automatic impedance matching system comprises the following steps:
1) establishing a three-pin waveguide equivalent circuit;
2) establishing a circuit parameter relationship;
3) and (4) designing a matching algorithm.
Preferably, R in step 1) is the radius of the pin; l1、l2、l3、l4Is the waveguide length between the pins; l, W and H are the length, width and height of the waveguide;
the step 1) comprises the following steps:
a. a single pin is equivalent to a capacitor connected in parallel, and the structure of the capacitor is as follows;
the relationship between the capacitive reactance and the insertion depth is
C＝0.3272tan(0.0452h) (1)
Having a chain scattering parameter of
Wherein C is a capacitance value, Z0Is the characteristic impedance of the transmission line, omega being the frequency
b. The other waveguides are equivalent to transmission lines, and the structure is as follows;
having a chain scattering parameter of
Wherein l is the length of the transmission line and β is the phase constant;
c. a section of transmission line and a capacitor form a basic unit, and the structure is as follows;
having a chain scattering matrix of
Wherein Ci is the capacitance value of the ith capacitor calculated according to the formula (1), and li is the length of the transmission line;
d. then, three equivalent parallel capacitors of the three pins and four equivalent series transmission lines of the waveguides are respectively cascaded, the inserted pins are equivalent to the capacitors connected in parallel, and the other waveguides are equivalent to the transmission lines, so that an equivalent circuit model formed by alternately cascading the three equivalent parallel capacitors and the four equivalent series transmission lines is established;
wherein l1、l2、l3、l4Respectively the waveguide lengths between corresponding pins in a common three-pin waveguide structure; c is the equivalent capacitance value of each pin. The chain scattering parameters are:
T＝[T1(C1，l1)][T2(C2，l2)][T3(C3，l3)][Ttrans(l4)] (5)
e. conversion from a chain scattering parameter T to a scattering parameter S
Wherein Δ T ═ T11T22-T12T21。
Preferably, according to the equivalent model and the scattering matrix in step 1), and in combination with the transmission line theory, the load impedance is obtained as follows:
wherein S11、S12、S21、S22The S parameters are respectively 4S parameters which are the reflection coefficients measured by the reflection coefficient measurer in the figure 1;
the reflection coefficient of the system for different pin depths and loads is:
preferably, the flow of the matching algorithm is as follows:
a. match status determination
The algorithm calculates whether the current standing wave coefficient VSWR is less than or equal to 1.2, if the standing wave coefficient is less than or equal to 1.2, the circuits are matched without adjustment; if the standing wave coefficient is larger than 1.2, the program enters the process of impedance matching adjustment, calculation is carried out after adjustment, and the adjustment is continued if the standing wave coefficient is larger than 1.2;
b. calculating equivalent capacitance and load impedance
The system can detect the reflection coefficient of the current incident end and the current pin depth, so that the program can calculate the S parameter of the current waveguide through a formula (6) and calculate the current load impedance through a formula (7);
c. simulating reflection coefficients at different pin depths
Under the condition of known S parameters and load impedance, a program can simulate the reflection coefficients of the incident ports under different pin depths, and finally, the condition of the minimum reflection coefficient is selected as a final solution;
d. adjusting the position of the pin
The program will control the stepper motor to adjust to the calculated position to achieve impedance matching.
Compared with the prior art, the invention has the beneficial effects that: the invention adopts an equivalent circuit analysis method, reduces the use of finite element simulation, and can quickly calculate the parameters of the waveguide according to the insertion depth of the pin, so the design process is simple, the complicated simulation and measurement can be avoided, and only the equivalent circuit parameters need to be modified according to different waveguide sizes, thereby having certain universal applicability.
Drawings
FIG. 1 is a flow chart of a fast three-pin automatic impedance matching algorithm
FIG. 2 is a diagram of a model of a validation experiment.
Fig. 3 shows different sizes of membranes.
Fig. 4 is a graph comparing calculated and measured parameters S. The left graph represents the amplitude of the S-parameter, the right graph represents the phase of the S-parameter, the solid black line represents the program calculated value, and the dashed black line represents the measured value.
Detailed Description
The technical scheme of the invention is further described in detail by combining the drawings and the detailed implementation mode:
the impedance matching system can be used for various microwave energy transmission devices, and the impedance can be adjusted only by connecting the system between a microwave source and a load.
The experimental model for validation is shown in FIG. 2.
We simulated different load impedances with different sized diaphragms as shown in fig. 3. The impedance of each diaphragm is different, so that different diaphragms represent different loads.
S parameter calculation test
Comparing the calculated S-parameters with the measured S-parameters, as shown in fig. 4, we found that the calculated results and the measured results have a high degree of consistency.
2. Testing of matching effects
TABLE 1 results of each match
As can be seen from Table 1, the reflection coefficients after the blending are greatly reduced compared with the reflection coefficients before the blending and are all below-10 dB, so that the effectiveness of the system is verified.
The above description is only an embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that are not thought of through the inventive work should be included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope defined by the claims.
Claims (3)
1. A rapid three-pin automatic impedance matching system is characterized by comprising the following steps:
1) establishing a three-pin waveguide equivalent circuit model:
r is the radius of the pin; l1、l2、l3、l4Is the waveguide length between the pins; l, W and H are the length, width and height of the waveguide;
comprises the following steps:
a. a single pin is equivalent to a parallel capacitor;
the relationship between the capacitive reactance and the insertion depth is as follows:
C＝0.3272tan(0.0452h) (1)
the chain scattering parameters are:
wherein C is a capacitance value, Z0Is the characteristic impedance of the transmission line, omega is the frequency, h is the insertion depth;
b. the rest waveguides are equivalent to series-connected transmission lines;
the chain scattering parameters are:
wherein l is the length of the transmission line and β is the phase constant;
c. cascading a series transmission line and a parallel capacitor to form a basic unit;
the chain scattering matrix is:
wherein C isiIs the capacitance value of the ith capacitor, l, obtained according to equation (1)iIs the length of the transmission line;
d. then, three equivalent parallel capacitors of the three pins and four equivalent series transmission lines of the waveguides are respectively cascaded, the inserted pins are equivalent to the capacitors connected in parallel, and the other waveguides are equivalent to the transmission lines, so that an equivalent circuit model formed by alternately cascading the three equivalent parallel capacitors and the four equivalent series transmission lines is established;
wherein l1、l2、l3、l4The lengths of the waveguides between the corresponding pins in the three-pin waveguide structure are respectively; c is the equivalent capacitance value of each pin;
the chain scattering parameters are:
T＝[T1(C1，l1)][T2(C2，l2)][T3(C3，l3)][Ttrans(l4)] (5)
e. conversion from a chain scattering parameter T to a scattering parameter S
Wherein Δ T ═ T11T22-T12T21；
2) Establishing a circuit parameter relationship;
3) and (4) designing a matching algorithm.
2. The fast three-pin automatic impedance matching system according to claim 1, wherein the load impedance obtained by combining the transmission line theory according to the equivalent circuit model and the chain scattering matrix of step 1) is:
wherein S11、S12、S21、S22The S parameters are respectively 4S parameters and are the reflection coefficients measured by a reflection coefficient measurer;
the reflection coefficient of the system for different pin depths and loads is:
3. the system of claim 2, wherein the matching algorithm is performed by the following steps:
a. match status determination
The algorithm calculates whether the current standing wave coefficient VSWR is less than or equal to 1.2, if the standing wave coefficient is less than or equal to 1.2, the circuits are matched without adjustment; if the standing wave coefficient is larger than 1.2, the program enters the process of impedance matching adjustment, calculation is carried out after adjustment, and the adjustment is continued if the standing wave coefficient is larger than 1.2;
b. calculating equivalent capacitance and load impedance
The system can detect the reflection coefficient of the current incident end and the current pin depth, so that the program can calculate the S parameter of the current waveguide through a formula (6) and calculate the current load impedance through a formula (7);
c. simulating reflection coefficients at different pin depths
Under the condition of known S parameters and load impedance, a program can simulate the reflection coefficients of the incident ports under different pin depths, and finally, the condition of the minimum reflection coefficient is selected as a final solution;
d. adjusting the position of the pin
The program will control the stepper motor to adjust to the calculated position to achieve impedance matching.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911267864.9A CN111062184B (en) | 2019-12-11 | 2019-12-11 | Quick three-pin automatic impedance matching system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911267864.9A CN111062184B (en) | 2019-12-11 | 2019-12-11 | Quick three-pin automatic impedance matching system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN111062184A CN111062184A (en) | 2020-04-24 |
| CN111062184B true CN111062184B (en) | 2020-12-01 |
Family
ID=70300567
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201911267864.9A Active CN111062184B (en) | 2019-12-11 | 2019-12-11 | Quick three-pin automatic impedance matching system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111062184B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113341810A (en) * | 2021-06-09 | 2021-09-03 | 四川大学 | Microwave energy intelligent controller |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104810935A (en) * | 2015-05-12 | 2015-07-29 | 南京信息工程大学 | Resonant coupling type wireless power multi-load transmission method |
| CN105490136A (en) * | 2016-01-13 | 2016-04-13 | 中国科学院半导体研究所 | Directly modulated laser micro-strip preparation method as well as micro-strip and laser obtained by using same |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3947406B2 (en) * | 2002-02-15 | 2007-07-18 | 株式会社ルネサステクノロジ | Semiconductor laser module |
| US6922071B2 (en) * | 2002-12-27 | 2005-07-26 | Intel Corporation | Setting multiple chip parameters using one IC terminal |
| US7398499B2 (en) * | 2006-05-24 | 2008-07-08 | Chang Gung University | Method of searching paths suffering from the electrostatic discharge in the process of an integrated circuit design |
| CN101217096B (en) * | 2007-01-04 | 2010-09-08 | 北京北方微电子基地设备工艺研究中心有限责任公司 | A quick RF automatic impedance matching method |
| CN103353553B (en) * | 2013-06-28 | 2016-05-25 | 四川大学 | The dielectric coefficient microwave measurement system of dielectric coefficient MMU microwave measurement unit and formation thereof |
| CN103587130B (en) * | 2013-10-15 | 2016-04-06 | 南京航空航天大学 | The method of microwave curing fiber-reinforced resin matrix compound material component and device |
| CN107770951A (en) * | 2017-11-08 | 2018-03-06 | 惠州市兴顺和电子有限公司 | High characteristic impedance multilayer circuit board and preparation method |
-
2019
- 2019-12-11 CN CN201911267864.9A patent/CN111062184B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104810935A (en) * | 2015-05-12 | 2015-07-29 | 南京信息工程大学 | Resonant coupling type wireless power multi-load transmission method |
| CN105490136A (en) * | 2016-01-13 | 2016-04-13 | 中国科学院半导体研究所 | Directly modulated laser micro-strip preparation method as well as micro-strip and laser obtained by using same |
Also Published As
| Publication number | Publication date |
|---|---|
| CN111062184A (en) | 2020-04-24 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104237829B (en) | Overall calibration method for high-accuracy noise factor measuring system | |
| Rolfes et al. | Multiport method for the measurement of the scattering parameters of N-ports | |
| CN111929558B (en) | Self-calibration-based de-embedding method, system, storage medium and terminal | |
| CN110646674B (en) | Radio frequency chip pin impedance test method | |
| CN111062184B (en) | Quick three-pin automatic impedance matching system | |
| JPH09243688A (en) | Method for measuring electronic object to be measured | |
| CN112098791B (en) | On-chip calibration piece model and method for determining parameters in on-chip calibration piece model | |
| CN104865453A (en) | Terahertz on-chip scattering parameter measurement calibration piece and preparation method thereof | |
| CN104378085A (en) | RF impedance matching debugging method | |
| CN111983539A (en) | On-chip S parameter measurement system calibration method | |
| CN107076822B (en) | Test structure and method for judging de-embedding precision of radio frequency device by using lead-in device | |
| CN103048550A (en) | Test system and test data calibration method of S-parameter of surface mount microwave device | |
| CN113435147B (en) | Lumped parameter negative group delay circuit and chip | |
| KR101831824B1 (en) | Method for correcting measurement error and device for measuring electronic component characteristics | |
| Wu et al. | The match game: Numerical de-embedding of field simulation and parameter extraction of circuit models for electromagnetic structure using calibration techniques | |
| CN109037872B (en) | Waveguide circulator power test system with low power source requirement | |
| CN111781479A (en) | On-wafer calibration piece model building method | |
| CN116449183B (en) | De-embedding structure and method for on-chip test of radio frequency chip, storage medium and terminal | |
| CN112597657A (en) | Method for designing millimeter wave S parameter transmission amplitude standard device | |
| Daywitt | Determining adapter efficiency by envelope averaging swept frequency reflection data | |
| Stewart et al. | Microstrip discontinuity modeling | |
| TWI842301B (en) | Impedance transfer circuit and radio frequency power reliability testing system | |
| Yang et al. | Design of a Millimeter-wave Bandpass Filter with Computer-aided Tuning Method | |
| Singh et al. | Comparison of Vector Network Analyser (VNA) calibration techniques at microwave frequencies | |
| CN116029247A (en) | Path planning method for three-pin impedance adjuster |
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 | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |