CN-121743902-B - Three-pin impedance matching method and device based on quick table lookup

CN121743902BCN 121743902 BCN121743902 BCN 121743902BCN-121743902-B

Abstract

The invention relates to the technical field of impedance matching of microwave sources, in particular to a three-pin impedance matching method and device based on quick table lookup. The method comprises the steps of constructing a mapping relation table of three pin insertion depths and impedance, splitting and sorting to form a real part impedance matching table and an imaginary part impedance matching table, obtaining electric parameters between a microwave source and the three pin matching device or between the three pin matching device and a load, calculating load impedance, searching index positions which are conjugate matched with the load impedance in the real part impedance matching table and the imaginary part impedance matching table, outputting the three pin insertion depths of matching data items where the index positions are located, and gradually widening the index range until the matching data items are found when the index ranges are not matched, and outputting the three pin insertion depths of the matching data items. The invention optimizes the data structure and the lookup logic of the table, reduces the data volume during the lookup, obviously improves the efficiency and the speed of impedance matching, and ensures the transmission of microwave signals.

Inventors

DENG QIANG
LUO JIE
XIAO YAO
LIU YANG
TANG JINCHENG

Assignees

四川英杰电气股份有限公司

Dates

Publication Date: 20260505
Application Date: 20260302

Claims (10)

1. A three pin impedance matching method based on a quick look-up table, the method comprising the steps of: s1, constructing a mapping relation table of the insertion depth of the three pins and the impedance of the three pins; sequencing the real part of the three-pin impedance and the imaginary part of the three-pin impedance in the mapping relation table in the same sequencing mode to form a real part impedance matching table and an imaginary part impedance matching table; s2, acquiring electrical parameters between the microwave source and the three-pin matcher or between the three-pin matcher and a load, and calculating load impedance; S3, searching a real part index position and an imaginary part index position which are conjugate-matched with the load impedance in the real part impedance matching table and the imaginary part impedance matching table respectively; If the real part index position and the imaginary part index position point to the same data item, outputting three pin insertion depths corresponding to the data item; If the real part index position and the imaginary part index position do not point to the same data item, gradually widening preset index ranges of the real part index position and the imaginary part index position according to gradients until the real part index position and the imaginary part index position pointing to the same data item can be extracted from the two widened index ranges, and outputting three pin insertion depths corresponding to the data item.
2. The rapid lookup table-based three-pin impedance matching method of claim 1, wherein the mapping table only retains data of a first pin insertion depth of 0 or a third pin insertion depth of 0 when the pin pitch of the three pins is 1/4 of the waveguide wavelength.
3. The three-pin impedance matching method based on the quick lookup table as claimed in claim 1, wherein when the real part index position and the imaginary part index position which are conjugate-matched with the load impedance are found in the real part impedance matching table and the imaginary part impedance matching table, a dichotomy is adopted for finding.
4. The three-pin impedance matching method based on the quick lookup table as claimed in claim 1, wherein in S3, if the number of data items pointing to the real index position and the imaginary index position of the same data item is plural, the matching errors of the plural data items are compared, and the three-pin insertion depth corresponding to the data item with the smallest matching error is taken as the output result.
5. The three pin impedance matching method based on a quick look-up table as recited in claim 4, wherein said matching error is calculated by the following formula: Wherein, the Is the matching error; Impedance for the three pins; is the load impedance.
6. The three-pin impedance matching method based on the quick lookup table as claimed in claim 1, wherein in the step S1, the three-pin matcher is regarded as a two-port network, scattering parameters corresponding to any insertion depth of the three-pin matcher are obtained by using an analyzer, a corresponding relation table of the scattering parameters and the insertion depth is established, and the three-pin impedance is calculated by the following formula: In the formula, Impedance for the three pins; Is the characteristic impedance of the three pins; And after calculating the three-pin impedance corresponding to the scattering parameter according to the corresponding relation table of the scattering parameter and the insertion depth, establishing a mapping relation table of the insertion depth of the three pins and the three-pin impedance.
7. The rapid lookup table-based three-pin impedance matching method according to claim 1, wherein the real part impedance matching table is arranged in an ascending or descending order according to the real part size of the three-pin impedance in a single column, and the real part index position and the imaginary part index position are both row numbers, or the real part impedance matching table is arranged in an ascending or descending order according to the real part size of the three-pin impedance in a single column, and the real part index position and the imaginary part index position are both column numbers.
8. The three pin impedance matching method based on the quick look-up table according to claim 6, wherein in S2, the reflection coefficient is calculated by the electrical parameter, and then the load impedance is calculated by the following formula: Wherein, the Is the load impedance; Is the characteristic impedance; Is the reflection coefficient of the load end; 、、、 Are both scattering coefficients of a two-port network.
9. The three-pin impedance matching method based on the quick lookup table as claimed in claim 1, further comprising S4, controlling the three-pin matcher to adjust pins to corresponding positions according to the insertion depth of the three pins so as to complete impedance matching.
10. A three pin impedance matching device based on a fast look-up table, comprising at least one processor and a memory communicatively coupled to the at least one processor, the memory storing instructions executable by the at least one processor to enable the at least one processor to perform a three pin impedance matching method based on a fast look-up table as claimed in any one of claims 1 to 9.

Description

Three-pin impedance matching method and device based on quick table lookup Technical Field The invention relates to the field of impedance matching of microwave sources, in particular to a three-pin impedance matching method and device based on a quick table lookup. Background In a microwave system, impedance matching of a load and a microwave source is a key premise for achieving optimal transmission of a power signal. In the prior art, a mapping relation database of three-pin insertion depth and load impedance is generally established through finite element method simulation or experimental measurement, reflection coefficients are obtained by means of a six-port device or a double directional coupler, the load impedance is calculated, then the three-pin target insertion depth is determined through table lookup, and finally the matcher is controlled to complete impedance matching. However, the prior art has the remarkable defects that on one hand, a mapping relation database of three pin depths and load impedance contains a large amount of arrangement and combination data, so that the table scale is huge, on the other hand, a table lookup algorithm is old, matching data is searched by adopting a mode of polling to traverse the whole array, the table lookup efficiency is low, the adjustment speed of the three pin matcher is slow, the application requirement of the industrial field on quick response of impedance matching is difficult to meet, and the efficient operation of a microwave system in an actual scene is limited. The prior document CN116029247A provides a path planning method of a three-pin impedance adjuster, and belongs to the technical field of impedance matching in the field of microwave energy application. The method comprises the steps of calculating the optimal solutions of the depths of three pins according to the reflection coefficient measured by the port when the load changes, and then implementing a low reflection adjustment strategy to adjust the depths of the three pins according to the calculated optimal solutions of the depths of the three pins so as to avoid large reflection in the adjustment process. However, the method does not perform data screening optimization on the mapping relation table of the three-pin impedance matching, and still adopts the old table lookup algorithm of polling traversal, so that the problems of large data size of the matching table and low table lookup efficiency are solved, the three-pin impedance matching adjustment speed is low, and the high-efficiency application requirements in the industrial field cannot be met. Disclosure of Invention The invention aims to solve the problems of high data volume of a matching table, low table lookup efficiency and low matching adjustment speed caused by old table lookup algorithm in the existing microwave system, and provides a three-pin impedance matching method and device based on quick table lookup. In a first aspect, the present invention provides a three pin impedance matching method based on a fast look-up table, the method comprising the steps of: s1, constructing a mapping relation table of the insertion depth of the three pins and the impedance of the three pins; Sequencing the real part of the three-pin impedance and the imaginary part of the three-pin impedance in the mapping relation table in the same sequencing mode to form a real part impedance matching table and an imaginary part impedance matching table; s2, acquiring electrical parameters between the microwave source and the three-pin matcher or between the three-pin matcher and a load, and calculating load impedance; s3, searching a real part index position and an imaginary part index position which are conjugate-matched with the load impedance in the real part impedance matching table and the imaginary part impedance matching table respectively; If the real part index position and the imaginary part index position point to the same data item, outputting three pin insertion depths corresponding to the data item; If the real part index position and the imaginary part index position do not point to the same data item, gradually widening preset index ranges of the real part index position and the imaginary part index position according to gradients until the real part index position and the imaginary part index position pointing to the same data item can be extracted from the two widened index ranges, and outputting three pin insertion depths corresponding to the data item. By constructing the split ordered real part and imaginary part impedance matching table and combining the strategy of conjugate matching index searching and gradual widening, the table searching logic is optimized, the pertinence and feasibility of matching searching are improved, the time consumption of table searching is reduced, and the impedance matching efficiency is improved. Preferably, the mapping table only retains data of the first pin insertion depth of 0 or the third p