KR101283232B1 - Apparatus and method for matching an impedance - Google Patents

Abstract

In the impedance matching method according to an exemplary embodiment of the present invention, a search region including an impedance value of a first impedance variable element and an impedance value of a second impedance variable element is divided into a plurality of regions, and a first region is formed in the plurality of regions. Setting search points; Detecting a first matched search point that is a search matched point among the first search points; Setting second search points, which are next search points, around the first search point, and detecting a second matched search point that is a next search match point among the second search points; And setting the next search points and detecting the next search match point, reducing the distance between the search points and ending the search for the impedance match point if the distance satisfies a predetermined condition. Includes steps

Description

Impedance Matching Device and Method {APPARATUS AND METHOD FOR MATCHING AN IMPEDANCE}

The present invention relates to an impedance matching device, and more particularly, to an impedance matching device mounted on a mobile terminal such as a mobile phone and searching for an optimum impedance matching point.

Mobile terminals such as mobile phones are equipped with an impedance matching device that automatically performs frequency tuning. The impedance matching device automatically finds the optimum capacitance value by sequentially changing the capacitance values of the built-in variable capacitor elements to find the optimum frequency. In this case, since the initial capacitance value of the variable capacitor devices is always set to a middle value of a changeable range, a method of finding impedance matching is always used starting from a fixed value regardless of the previous impedance matching value.

However, in the conventional impedance matching method, the impedance matching device searches for a point where the intensity of the reflected wave is minimized while sequentially changing the values of the variable capacitors at predetermined intervals, and thus, it takes a long time and consumes a lot of power.

In addition, the impedance matching device applies a control signal to the variable capacitors to find the optimum capacitance value, that is, the tuned capacitance value, while changing the capacitance value. do.

The present invention provides a method for high speed processing of impedance matching of an impedance matching device.

The present invention relates to an impedance matching method of an antenna impedance matching device including a first impedance variable element and a second impedance variable element, the search comprising an impedance value of the first impedance variable element and an impedance value of the second impedance variable element. Dividing an area into a plurality of areas and setting first search points in the plurality of areas; Detecting a first matched search point that is a search matched point among the first search points; Setting second search points, which are next search points, around the first search point, and detecting a second matched search point that is a next search match point among the second search points; And setting the next search points and detecting the next search match point, reducing the distance between the search points and ending the search for the impedance match point if the distance satisfies a predetermined condition. It provides an impedance matching method comprising the step.

In addition, the present invention provides an impedance matching device of an antenna, comprising: a first impedance variable element; A second impedance variable element; A detector detecting signal power of the antenna; And a controller configured to control an impedance value of the first impedance variable element and an impedance value of the second impedance variable element based on the signal power, wherein the impedance value of the first impedance variable element and the second impedance variable element are controlled. Determine a first search matching point among the first search points set in the plurality of areas constituting the search area composed of the impedance value of, set the next search points around the first search match point, and the next search An impedance matching device is characterized in that the impedance matching point is determined by reducing the distance between the searching points using a process of detecting a next search matching point among the points.

In addition, the present invention provides a computer-readable recording medium storing a program for impedance matching, wherein a search area composed of an impedance value of a first impedance variable element and an impedance value of a second impedance variable element is divided into a plurality of regions. Setting first search points in the plurality of areas; Detecting a first matched search point that is a search matched point among the first search points; Setting second search points, which are next search points, around the first search point, and detecting a second matched search point that is a next search match point among the second search points; And setting the next search points and detecting the next search match point, reducing the distance between the search points and ending the search for the impedance match point if the distance satisfies a predetermined condition. A computer readable recording medium having stored therein a program is provided.

According to an embodiment of the present invention, the search section may be adaptively changed than the conventional algorithm, thereby improving the impedance matching speed of the impedance matching device.

Meanwhile, various other effects will be directly or implicitly disclosed in the detailed description according to the embodiment of the present invention to be described later.

1 is a block diagram of an impedance matching device according to an embodiment of the present invention;
2 is a diagram illustrating an impedance matching method according to a first embodiment of the present invention;
3 is a diagram illustrating a method of searching for an impedance matching point in the impedance matching method of FIG. 2;
4A to 4D illustrate an impedance matching method according to a second embodiment of the present invention;
5 is a flowchart of a procedure of performing the impedance matching method of FIG. 4.

In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear. The following terms are defined in consideration of the functions of the present invention, and may be changed according to the intentions or customs of the user, the operator, and the like. Therefore, the definition should be based on the contents throughout this specification.

An embodiment of the present invention provides a method for fast processing impedance matching of an impedance matching device.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

1 shows a configuration of an impedance matching device according to an embodiment of the present invention.

Referring to FIG. 1, the impedance matching device 100 includes a variable element unit including a parallel capacitor 121a connected in parallel with an antenna, a series capacitor 121b connected in series, and inductor elements 122a, 122b, and 122c. 120, a directional coupler 130 for detecting a signal input to the impedance matching device and a signal reflected from the end of the antenna terminal, and a detector 140 measuring power of a signal input through the directional coupler 130. ), A control unit which generates a control signal of the variable capacitors 121a and 121b based on the forward power and the reflective power provided from the detector 140 and transmits the control signal to the variable element unit 120. 150 and an antenna 160 for transmitting and receiving RF signals.

The variable element unit 120 may include a plurality of variable capacitors 121a and 121b and a plurality of fixed inductors 122a, 122b and 122c. The number of wires or elements of the variable capacitors 121a and 121b and the fixed inductors 122a, 122b and 122c may vary according to embodiments. The variable capacitors 121a and 121b and the fixed inductors 122a, 122b and 122c together form an impedance of a device on which the impedance matching device 100 is mounted.

The values of the variable capacitors 121a and 121b are changed by the DC voltage applied by the controller 150, and the magnitude of the reflected signal with respect to the transmission signal is changed by the values of the converted variable capacitors 121a and 121b. Done.

In general, assuming that the input signal is constant, the larger the size of the reflected signal, the poorer the impedance matching is, and the smaller the size of the reflected wave signal, the better the impedance matching is achieved.

Meanwhile, in the present exemplary embodiment, the variable capacitors 121a and 121b are exemplified as one parallel capacitor 121a and one series capacitor 121b, but the present invention is not limited thereto. The parallel capacitor 121a or the series capacitor is not limited thereto. It may consist of only 121b, it may be composed of three or more variable capacitors.

The detector 140 measures the magnitude of the signal input to the antenna terminal 160 and the magnitude of the signal reflected from the end of the antenna 160. At this time, the detector 140 measures the voltage or power value of the input signal and the reflected signal.

An analog / digital converter (not shown) converts an analog signal input from the detector 140 into a digital signal and provides the converted signal to the controller 150. In this case, an analog / digital converter (not shown) may be implemented in the controller 150.

The controller 150 applies a control signal of the variable capacitors 121a and 121b based on the transmission power and the reflection power to change the impedance value of the variable element unit 120 to perform impedance matching. In this case, since the controller 150 includes a digital-to-analog converter (not shown), the controller 150 converts the digital signal into an analog signal and provides the converted signal to the variable element unit 120.

However, in the conventional impedance matching algorithm, the controller 150 changes the capacitance values of the variable capacitors 121a and 121b in order at regular intervals, and searches for a point where the intensity of the reflected signal is minimized. There is also a lot of power consumption.

In addition, the controller 150 applies a control signal to the variable capacitors 121a and 121b to find an optimal capacitance value, that is, a tuned capacitance value while changing the capacitance value. In this case, the variable capacitors 121a and 121b It is a question of which range to change the capacitance value of?).

In order to solve this problem, the following embodiments provide an impedance matching algorithm more efficient than the conventional impedance matching algorithm.

2 shows an impedance matching method according to a first embodiment of the present invention.

Referring to FIG. 2, the x-axis is the capacitance value of the first variable capacitor, and the y-axis is the capacitance value of the second variable capacitor.

First, when the impedance matching device performs impedance matching, the first search region 211 is set based on the point 224 corresponding to the middle value of the variable range of the first variable capacitor and the second variable capacitor.

The search is performed on the first search area 211 so that the maximum difference between the magnitude of the forward signal and the reflect signal is found within the search area 211, that is, an optimal point or matched search. Find a point. In this case, the matching search point may be set to a point where the size of the reflected signal is minimum or a point where the size ratio of the size of the transmitted signal and the reflected signal is minimum. In this case, the search means measuring the difference between the transmission signal and the reflected signal by using values of the first and second variable capacitors corresponding to the search area in sequence.

The first search region 211 may be set to have a square shape, and a length of one side of the square, that is, a range in which the variable capacitor may be changed may vary according to embodiments.

In addition, the inside of the first search region 211 may be divided into a plurality of sections, that is, 16 sections (4 × 4), and the length of one section of the plurality of sections may also vary according to embodiments. .

Meanwhile, in FIG. 2, it is assumed that the M point 221 is an impedance matching point, that is, a point at which the difference between the magnitude of the transmission signal and the magnitude of the reflected signal is maximum. In addition, it is assumed that a region 231 having a weaker reflected wave intensity and a region 232 having a stronger reflected wave intensity are arranged around the M point 221 in a contour form.

As the distance from the M point 221 increases, the value of the reflected wave becomes larger. Therefore, when the search is performed in the first search area 211, the first closest to the M point 221 in the first search area 211 is performed. The reflected wave value at matched search point 223 will be minimal.

When the matching search point 223 in the first search area 211 is determined, a second search area 212 is set around the matching search point 223. In this case, as shown in FIG. 2, the second search area 212 may be set to have the same square shape as the first search area 211. In addition, the second search area 212 is positioned in the direction of the M point 221 with respect to the first search area 211.

The impedance matching device performs a search on the second search area 212 to determine the matching search point 222 in the second search area 212.

Thereafter, a third search area 213 is set in the direction of the M point 221 around the matching search point 222 in the second search area 212, and the third search area 213 is set. Perform a search. In this case, as illustrated in FIG. 2, the third search region 213 may be set to have the same square shape as the first search region 211.

Since the third search region 213 includes the impedance matching point 221, a change in the reflected wave intensity decreases and then increases within the region. In other words, while changing the capacitance value of the variable capacitor in one direction, it is possible to find a point where the change in the reflected wave intensity changes, which is the impedance matching point 221.

When the impedance matching point 221 is determined, the impedance matching device performs impedance matching with the capacitance value of the variable capacitor corresponding to the point.

In the present exemplary embodiment, the first search area 211 to the third search area 213 are set to have a square shape, but the present invention is not limited thereto and may be set to another shape.

On the other hand, within the search region, the method of finding the matching search point proceeds from the lower direction to the upper direction while moving from the left section to the right section. For example, as shown in FIG. 3, within the corresponding search area, the search for the matching search point starts at the bottom left section and ends at the top right section.

However, in the search method, even if the impedance matching point has a distance from the current point, a problem arises in that a predetermined section must be searched, thereby degrading the performance of the impedance matching device, and it may take a long time to find the impedance matching point.

In order to improve the above, another embodiment of the present invention will be described with respect to the impedance matching method for finding the impedance matching point by setting a plurality of search points based on the matching search point, and reducing the distance between the search points step by step Explain.

4A to 4D illustrate an impedance matching method according to a second embodiment of the present invention.

4A to 4D, the x axis represents the capacitance value of the first variable capacitor, and the y axis represents the capacitance value of the second variable capacitor. At this time, the variable range of the x-axis and y-axis is illustrated as being divided into 16 equal intervals, but is not limited thereto.

On the other hand, in the present embodiment, the impedance matching point, that is, the point where the difference between the magnitude of the forward signal and the reflective signal is maximum is the point 401 whose values of the x-axis and the y-axis are (11, 9). It is assumed that this is explained.

First, referring to FIG. 4A, the entire search area 410 is divided into four equal areas, and the center point of each area is set as the first search points ① to ④. In this case, it is preferable that the entire search area is set in a square shape in which the variable ranges of the x-axis and the y-axis are the same.

In addition, the horizontal distance or the vertical distance between the first search points is set to D / 2. In this case, the D corresponds to the entire section of the variable range of the x-axis or y-axis, and in the present embodiment will be described on the assumption that D is 16.

The impedance matching device finds a point (that is, an optimum point or a matching search point) among the first search points ① to ④ having a maximum difference between the magnitudes of the transmission signal and the reflected signal. In this case, the matching search point may be set to a point where the size of the reflected signal is minimum or a point where the size ratio of the size of the transmitted signal and the reflected signal is minimum.

In general, since the magnitude of the reflected signal increases as the distance from the impedance matching point 401 increases, when the impedance matching device searches for the first search points ① to ④, the impedance matching point 401 is the most. The size of the reflected signal measured at point 3 closest to will be minimal.

The impedance matching device sets the third point as the first matching search point ③. When the first match search point ③ is determined, a second search point is set based on the first match search point ③.

Referring to FIG. 4B, four corner points of the square region 420 having a length D / 2 around the first matching search point ③ are set as the second search points. In this case, the second search point includes the first matching search point ③.

The impedance matching device finds a point where the difference in magnitude between the transmitted signal and the reflected signal is the largest among the second search points ③ and ⑤ to ⑧.

Since the magnitude of the reflected signal increases as the distance from the impedance matching point 401 increases, when the impedance matching device searches for the second search points ③, ⑤ to ⑧, the impedance matching point 401 The reflected signal measured at point 5 near it will be the smallest.

The impedance matching device sets the fifth point as the second matching search point ⑤. When the second matching search point ⑤ is determined, a third search point is set based on the second matching search point ⑤.

Referring to FIG. 4C, four corner points of the square region 430 having a length D / 4 around the second matching search point ⑤ are set as the third search points. In this case, the third search point includes the second matching search point ⑤.

The impedance matching device finds a point where the difference in magnitude between the transmitted signal and the reflected signal is the largest among the third search points ⑤ and ⑨ to ⑫.

Since the magnitude of the reflected signal increases as the distance from the impedance matching point 401 increases, when the impedance matching device searches for the third search points ⑤, ⑨ to ⑫, the impedance matching point 401 The magnitude of the reflected signal measured at point 11 near it will be minimal.

The impedance matching device sets point 11 as the third matching search point. When the third match search point is determined, a fourth search point is set based on the third match search point.

Referring to FIG. 4D, four corner points of the square area 440 having a length D / 8 around the third matching search point ⑪ are set as the fourth search points. In this case, the fourth search point includes the third matching search point.

The search point is repeatedly set until D / n = 2, (n = 1, 2, 4, 8, ...), that is, until the distance between the search points becomes 2. In the present embodiment, since the value of D is 16, the impedance matching device sets the fourth search point as the last search point. When the search for the last set point is completed, the corresponding algorithm is terminated.

)중 전송 신호와 반사 신호의 크기 차이가 최대인 지점을 찾는다. 본 실시 예에서, 임피던스 정합 지점은 x축과 y축의 값이 (11, 9)인 지점(401)이기 때문에, 상기 16번 지점에서 가장 작은 반사 신호의 크기를 갖게 된다. 즉, 상기 16번 지점에서, 전송 신호의 크기와 반사 신호의 크기 차이가 최대가 되며, 해당 지점이 임피던스 정합 지점(401)이 된다.The impedance matching device includes the fourth search points (⑪, ⑬ ~ ⑬).

), Find the point where the difference between the transmitted signal and the reflected signal is the largest. In the present embodiment, since the impedance matching point is the point 401 whose values of the x-axis and the y-axis are (11, 9), it has the smallest reflected signal at the 16th point. That is, at the point 16, the difference between the magnitude of the transmission signal and the magnitude of the reflected signal is maximized, and the point becomes the impedance matching point 401.

When the impedance matching point 401 is determined, the impedance matching device performs impedance matching with the capacitance value of the variable capacitor corresponding to the point 401.

5 is a flowchart of a procedure of performing the impedance matching method of FIG. 4.

Referring to FIG. 5, in step 510, the impedance matching apparatus divides the entire search area into four equal areas, and sets the center point of each area as the first search point. In this case, it is preferable that the entire search area is set in a square shape in which the variable ranges of the x-axis and the y-axis are the same.

In addition, the horizontal distance or the vertical distance between the first search points is set to D / 2. In this case, the D corresponds to the entire length of the variable range of the x-axis or y-axis.

In operation 520, the impedance matching device finds a point (ie, a first matching search point) having a maximum difference between the magnitudes of the transmission signal and the reflected signal among the first search points. In this case, the matching search point may be set to a point where the size of the reflected signal is minimum or a point where the size ratio of the size of the transmitted signal and the reflected signal is minimum.

If the first match search point is determined, step 530 is reached.

In step 530, the impedance matching device sets a second search point based on the first match search point. That is, the impedance matching device sets four corner points of the square area having a length D / 2 around the first matching search point as the second search point. In this case, the second search point includes the first match search point.

In operation 540, the impedance matching apparatus finds a point (ie, a second matching search point) having a maximum difference between the magnitudes of the transmission signal and the reflected signal among the second search points.

If the second match search point is determined, step 550 is reached.

In step 550, the impedance matching device determines whether the distance between the search points is two. As a result of the determination, if the distance between the search points is not 2, the flow moves on to step 560.

In step 560, the impedance matching device sets four corner points of the square area having a length D / 4 around the second matching search point as the third search point. In this case, the third search point includes the second match search point.

In operation 570, a point (ie, a third matched search point) having a maximum difference between the magnitudes of the transmission signal and the reflected signal is found among the third search points.

When the third match search point is determined, the process returns to step 550 again.

In step 550, the impedance matching device determines whether the distance between the search points is two. As a result of the determination, if the distance between the search points is not 2, steps 560 and 570 are repeated.

On the other hand, if the distance between the search points as a result of the determination 2, go to step 580.

In step 580, the impedance matching device determines, as the impedance matching point, the point where the difference between the magnitude of the transmitted signal and the reflected signal is the largest among the last search points. Once this impedance matching point is determined, the algorithm is terminated.

The impedance matching device performs impedance matching with the capacitance value of the variable capacitor corresponding to the impedance matching point.

As described above, the impedance matching device may improve the impedance matching speed by setting a plurality of search points based on the matching search point and gradually reducing the distance between the search points.

While the invention has been shown and described with reference to certain preferred embodiments thereof, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be determined by equivalents to the appended claims, as well as the appended claims.

100: impedance matching device 120: variable element
121a: parallel variable capacitor 121b: series variable capacitor
122a, 122b, 122c: inductor element 130: directional coupler
140: detection unit 150: control unit
160: antenna

Claims (22)

An impedance matching method of an antenna impedance matching device including a first impedance variable element and a second impedance variable element,
Dividing a search region consisting of an impedance value of the first impedance variable element and an impedance value of the second impedance variable element into a plurality of regions, and setting first search points in the plurality of regions;
Detecting a first matched search point that is a search matched point among the first search points;
Setting second search points, which are next search points, around the first search point, and detecting a second matched search point that is a next search match point among the second search points; And
Reducing the distance between the search points by setting the next search points and detecting the next search match point, and ending the search for the impedance match point if the distance satisfies a predetermined condition. Impedance matching method comprising a. The method of claim 1,
The first search region has a square shape in which the x-axis representing the impedance value of the first impedance variable element and the y-axis representing the impedance value of the second impedance variable element have the same square shape. The method of claim 2,
When the entire section of the variable range of the x-axis or y-axis is D,
And a horizontal distance and a vertical distance between the first search points are D / 2. The method of claim 1, wherein detecting the first match search point comprises:
Impedance matching method for detecting the point of the maximum difference between the transmission signal and the reflected signal of the first search point. The method of claim 1, wherein the detecting of the second matching search point comprises:
Impedance matching method for detecting a point of the maximum difference between the transmission signal and the reflected signal of the second search points. The method of claim 3, wherein the setting of the second search points comprises:
And setting four corner points of the square area having the length D / 2 around the first match search point and the first match search point as the second search points. The method according to claim 6,
And said predetermined condition is a distance between said reduced search points is two. The method of claim 7, wherein
If the distance between the search points is 2,
Impedance matching method of determining the impedance matching point of the last search point is the maximum difference between the magnitude of the transmission signal and the reflected signal. The method of claim 1,
And the first search points are center points of the plurality of regions. Impedance matching device of the antenna,
A first impedance variable element;
A second impedance variable element;
A detector detecting signal power of the antenna; And
A control unit controlling an impedance value of the first impedance variable element and an impedance value of the second impedance variable element based on the signal power,
Determine a first search matching point among first search points set in a plurality of areas constituting a search area including an impedance value of the first impedance variable element and an impedance value of the second impedance variable element,
The impedance matching point may be determined by reducing the distance between the search points by setting next search points around the first search matching point and detecting a next search matching point among the next search points. Impedance Matching Device. The method of claim 10,
The first search region has a square shape in which a variable range of the x-axis representing the impedance value of the first impedance variable element and the y-axis representing the impedance value of the second impedance variable element is the same. The method of claim 11,
When the entire section of the variable range of the x-axis or y-axis is D,
And a horizontal distance and a vertical distance between the first search points are D / 2. 11. The apparatus according to claim 10,
The impedance matching device of the first search point to determine the point of the maximum difference between the magnitude of the transmission signal and the reflected signal as the first matching search point. 11. The apparatus according to claim 10,
And a second matching search point is determined as a point where the difference between the transmission signal and the reflected signal is the largest among the second search points. 13. The apparatus according to claim 12,
The first matching search point and the impedance matching device to set the four corner points of the square area having a length D / 2 around the first matching search point as the second search points. 16. The method of claim 15,
And the search for the impedance matching point is terminated when the distance between the reduced search points is two. 17. The apparatus of claim 16,
And an impedance matching point when the distance between the search points is 2, the point at which the difference between the transmission signal and the reflected signal is the largest among the last search points is determined as the impedance matching point. The method of claim 10,
And the matching search point is a point where the ratio of the magnitude of the transmitted signal to the magnitude of the reflected signal is minimum. The method of claim 10,
The impedance matching device of the first and second impedance variable elements are variable capacitors. The method of claim 10,
And a first impedance variable element connected in parallel with the antenna and the second impedance variable element connected in series with the antenna. A computer-readable recording medium storing a program for impedance matching,
Dividing a search region consisting of an impedance value of a first impedance variable element and an impedance value of a second impedance variable element into a plurality of regions, and setting first search points in the plurality of regions;
Detecting a first matched search point that is a search matched point among the first search points;
Setting second search points, which are next search points, around the first search point, and detecting a second matched search point that is a next search match point among the second search points; And
Reducing the distance between the search points by setting the next search points and detecting the next search match point, and ending the search for the impedance match point if the distance satisfies a predetermined condition. A computer readable recording medium having stored therein a program. An impedance matched antenna using the impedance matching device of claim 10.

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