Antenna equipment

Abstract

Replacing helical antennas with printed antennas in the automotive anti-theft sector. [Solution] An antenna device 1000 integrated into an electronic device 2000 and operating at a center frequency includes a substrate 50 and a conductive layer 80. The substrate 50 has a first surface 51. The conductive layer 80 is disposed on the first surface 51 of the substrate 50. The conductive layer 80 has a printed pattern 81 including a radiating element 100 and a matching element 200. The radiating element 100 has a plurality of meandering portions arranged along a first direction. Two adjacent meandering portions are substantially parallel to each other and electrically coupled. The matching element 200 has a plurality of protruding portions arranged along a first direction. Two adjacent protruding portions are substantially parallel to each other and electrically isolated.

Description

Technical Field

[0001] The present disclosure relates to an antenna device, and more particularly, to an antenna device having a form of a printed antenna and adapted for vehicle anti-theft applications.

Background Art

[0002] With the development of new energy and electric engines, various vehicles are widely used in daily life. To meet safety requirements, vehicles are usually equipped with anti-theft devices. Furthermore, the anti-theft device is provided with a transceiver for wireless communication to receive a remote control signal from the vehicle driver or to detect the movement of suspicious persons in the surrounding area.

[0003] Conventional vehicle anti-theft devices usually use a transceiver operating at a frequency of 315 MHz. Furthermore, the transceiver usually uses a helical antenna having a center frequency of 315 MHz.

[0004] However, the helical antenna of the vehicle anti-theft device has several drawbacks that can deteriorate the performance and lifespan of the vehicle anti-theft device. For example, particularly for trucks equipped with a diesel engine, long-term vibrations during vehicle travel may damage the helical antenna. Furthermore, in the manufacturing process of the vehicle anti-theft device, it is necessary to assemble and solder the helical antenna to a circuit board, increasing the manufacturing difficulty. In addition, the helical antenna is usually made of an elastic material, so the helical antenna may be stretched or deformed, resulting in a change in the size of the helical antenna.

[0005] Based on the above problems, it is desirable to have an improved antenna device in the vehicle anti-theft field that replaces the conventional helical antenna with a printed antenna and realizes a center frequency that meets the specifications required by users.

[0006] Disclosure of related technologies / References A related technology, Taiwan Patent Application Publication No. 202145641, titled "Meander Antenna Structure," published on December 1, 2021, provides an antenna structure. This antenna structure includes a substrate, a ground layer, and a microstrip antenna layer. The ground layer and microstrip antenna layer are arranged on both sides of the substrate. The microstrip antenna layer includes a radiating unit formed in a meander shape with a recess. The length of the radiating unit is equal to 0.8 to 1.2 wavelengths, corresponding to the operating frequency. When the input end of this radiating unit receives an input signal and generates an electromagnetic wave with radiated energy, its half-power beam width increases. [Overview of the project]

[0007] According to one embodiment of the present disclosure, an antenna device is provided. The antenna device operates at a center frequency and includes a substrate and a conductive layer. The substrate has a first surface. The conductive layer is located on the first surface of the substrate. The conductive layer has a printed pattern including radiating elements and matching elements. The radiating elements have a plurality of meandering portions arranged along a first direction. Two adjacent meandering portions are substantially parallel to each other and electrically coupled. Each meandering portion includes a first section extending along a second direction, a second section substantially parallel to the first section, and a third section extending along the first direction and electrically coupled to the first and second sections. Each of the first, second, and third sections has a strip shape, and the first, second, and third sections form a "U-turn" shape. The matching element has multiple protrusions arranged along a first direction, where two adjacent protrusions are substantially parallel to each other and electrically isolated. Each of the protrusions of the matching element is sandwiched between two adjacent meandering portions of the radiating element along a second direction, where the second direction is not parallel to the first direction. [Brief explanation of the drawing]

[0008] [Figure 1A] This is a schematic diagram of an antenna device 1000 according to an embodiment of the present disclosure. [Figure 1B] Figure 1A is a top view of the antenna device 1000 shown. [Figure 2A] This is a top view of the printed pattern 81 of the antenna device 1000. [Figure 2B] This is a top view of one of the meandering portions of the radiating element 100. [Figure 2C] This is a top view of one of the protruding portions of the matching element 200. [Figure 2D] This is a top view showing the relative arrangement of the protruding portion 210, the two adjacent meandering portions 130 and 140, and the ground contact area 300. [Figure 3]This is a schematic diagram showing multiple equivalent capacitors formed by the matching element 200 of the antenna device 1000. [Figure 4A] This figure shows the frequency characteristics of antenna device 1000. [Figure 4B] This figure shows the frequency characteristics of antenna device 1000.

[0009] In the following detailed description, several specific details are given for illustrative purposes to provide a full understanding of the disclosed embodiments. However, it is clear that one or more embodiments may be carried out without these specific details. In other cases, well-known structures and devices are shown schematically for the sake of simplicity in the drawings. [Modes for carrying out the invention]

[0010] Figure 1A is a schematic diagram of an antenna device 1000 according to one embodiment of the present disclosure. As shown in Figure 1A, the antenna device 1000 is integrated into an electronic device 2000. The electronic device 2000 is, for example, a transceiver for wireless communication and may be used for vehicle theft prevention applications. The electronic device 2000 includes a printed circuit board, which includes a substrate 50 and a conductive layer 80. The conductive layer 80 is located on a first surface 51 of the substrate 50. The antenna device 1000 of the present disclosure is formed by a portion of the substrate 50 and a portion of the conductive layer 80. The antenna device 1000 has the form of a printed antenna, and the conductive layer 80 has a predetermined printed pattern 81.

[0011] Figure 1B is a top view of the antenna device 1000 shown in Figure 1A. As shown in Figure 1B, the antenna device 1000 has a radiating region 100R. The radiating region 100R has a width W1 in a first direction X and a length L1 in a second direction Y. The first direction X is substantially perpendicular to the second direction Y. In this embodiment, the width W1 is smaller than the length L1. The width W1 is, for example, 10.5 mm, and the length L1 is, for example, 33 mm.

[0012] The printed pattern 81 is positioned corresponding to the radiation region 100R. The printed pattern 81 includes at least a radiating element 100, a matching element 200, and a grounding region 300. The radiating element 100 and the matching element 200 are positioned within the radiation region 100R, and the grounding region 300 is positioned along and near the boundary of the radiation region 100R. The antenna device 1000 can transmit and receive radio frequency signals by radiating electromagnetic waves through the radiating element 100. The radiating element 100 has, for example, a plurality of meandering patterns. In this embodiment, the radiating element 100 extends from a reference position P1 in the upper left corner to a reference position P2, along a direction opposite to the second direction Y. Furthermore, the radiating element 100 makes a turn of approximately 90 degrees at the reference position P2 and then extends along the first direction X. Then, the radiating element 100 makes another turn of approximately 90 degrees and extends along the second direction Y. Similarly, the radiating element 100 makes another approximately 90-degree turn and extends along the first direction X, then makes yet another approximately 90-degree turn and extends along the opposite direction of the second direction Y. This arrangement is repeated until the radiating element 100 extends to the reference position P3, and then reaches the reference position P4 along the second direction Y.

[0013] The matching element 200 extends along the second direction Y. The matching element 200 is electrically isolated from the radiating element 100. Furthermore, the matching element 200 is sandwiched between two adjacent meandering patterns of the radiating element 100. The grounding region 300 surrounds the radiating element 100 along the first direction X and the second direction Y. Furthermore, the grounding region 300 is electrically coupled to the matching element 200 in the first direction X. During operation, the matching element 200 can form multiple equivalent capacitors between the radiating element 100 and the grounding region 300. The antenna device 1000 operates at a predetermined center frequency due to these equivalent capacitances. The arrangement of the radiating element 100, the matching element 200, and the grounding region 300 in the printed pattern 81 will be described in further detail with reference to Figures 2A to 2C.

[0014] First, please refer to Figure 2A, which is a top view of the printed pattern 81 of the antenna device 1000. The radiating element 100 of the printed pattern 81 has a plurality of meandering portions, for example, six meandering portions 110 to 160, arranged along a first direction X. Two adjacent meandering portions 110 to 160 are substantially parallel to each other and electrically coupled. For example, meandering portion 110 is next to meandering portion 120, and meandering portion 110 is substantially parallel to meandering portion 120 and electrically coupled. Similarly, adjacent meandering portions 120 and 130 are substantially parallel to each other and electrically coupled. Similarly, adjacent meandering portions 150 and 160 are substantially parallel to each other and electrically coupled.

[0015] The matching element 200 has a plurality of protruding portions, for example, three protruding portions 210-230, arranged along a first direction X. Two adjacent protruding portions 210-230 are substantially parallel to each other and electrically isolated from each other. For example, adjacent protruding portions 210 and 220 are substantially parallel to each other and electrically isolated from each other, and adjacent protruding portions 220 and 230 are substantially parallel to each other and electrically isolated from each other. Furthermore, one of the protruding portions 210-230 of the matching element 200 is sandwiched between two adjacent meandering portions 110-160 of the radiating element 100 along a second direction Y. For example, protruding portion 210 is sandwiched between adjacent meandering portions 130 and 140 along the second direction Y. Protruding portion 220 is sandwiched between adjacent meandering portions 140 and 150 along the second direction Y. The protruding portion 230 is sandwiched between the adjacent meandering portions 150 and 160 along the second direction Y.

[0016] In contrast, one or more of the meandering portions 110-160 of the radiating element 100 are sandwiched between two adjacent protruding portions 210-230 of the matching element 200 along the second direction Y. For example, meandering portion 140 is sandwiched between adjacent protruding portions 210 and 220 along the second direction Y. Meandering portion 150 is sandwiched between adjacent protruding portions 220 and 230 along the second direction Y.

[0017] Next, please refer to Figure 2B, which is a top view of one of the meandering sections of the radiating element 100. As an example in Figure 2B, the meandering section 110 is used, which includes a first section 111, a second section 112, and a third section 113. Each of the first section 111, the second section 112, and the third section 113 has a strip-like shape. The length of the first section 111 is substantially equal to the length of the second section 112 (or, in another example, the length of the first section 111 is slightly greater than the length of the second section 112).

[0018] The first section 111 extends along the second direction Y. The second section 112 also extends along the second direction Y and is substantially parallel to the first section 111. The third section 113 extends along the first direction X and is electrically coupled to the first section 111 and the second section 112. According to the above arrangement, the first section 111, the second section 112, and the third section 113 form a "U-turn" pattern. Furthermore, the second section 112 of the meandering section 110 is electrically coupled to the adjacent meandering section 120 (the meandering section 120 is not shown in Figure 2B).

[0019] Next, please refer to Figure 2C, which is a top view of one of the protruding portions of the matching element 200. In the example of Figure 2C, a protruding portion 210 is used. The protruding portion 210 has a strip shape and has a first end 210e1 and a second end 210e2. The second end 210e2 is positioned on the opposite side of the first end 210e1 in the second direction Y.

[0020] Next, refer to FIG. 2D, which is a top view showing the relative arrangement of the protruding portion 210, two adjacent meandering portions 130 and 140, and the grounding region 300. The protruding portion 210 extends between two adjacent meandering portions 130 and 140 along the second direction Y at the second end 210e2. The length of the protruding portion 210 is shorter than the length of the first section 131 and the length of the second section 132 of the meandering portion 130. Similarly, the length of the protruding portion 210 is shorter than the length of the first section 141 and the length of the second section 142 of the meandering portion 140.

[0021] Furthermore, the protruding portion 210 is substantially parallel to the second section 132 of the meandering portion 130 and is electrically insulated. Similarly, the protruding portion 210 is substantially parallel to the first section 141 of the meandering portion 140 and is electrically insulated. Furthermore, the grounding region 300 is electrically coupled to the first end 210e1 of the protruding portion 210 along the first direction X.

[0022] As described above, during operation, the matching element 200 can form a plurality of equivalent capacitors between the radiating element 100 and the grounding region 300. For example, the protruding portion 210 of the matching element 200 forms an equivalent capacitor. This equivalent capacitor is equivalently coupled between the adjacent meandering portions 130 and 140 of the radiating element 100 and the grounding region 300. Hereinafter, the details of the matching element 200 that forms a plurality of equivalent capacitors will be described with reference to FIG. 3.

[0023] Figure 3 is a schematic diagram showing multiple equivalent capacitors formed by the matching element 200 of the antenna device 1000. As shown in Figure 3, the signal input terminal e_in of the antenna device 1000 is electrically coupled to the radiating element 100. The matching element 200 is positioned between the radiating element 100 and the ground area 300. The protruding portion 210 of the matching element 200 forms an equivalent capacitor C1. Equivalent capacitor C1 is equivalently coupled between the radiating element 100 and the ground area 300. Similarly, the other two protruding portions 220 and 230 of the matching element 200 form equivalent capacitors C2 and C3, respectively. Both equivalent capacitors C2 and C3 are equivalently coupled between the radiating element 100 and the ground area 300.

[0024] The antenna device 1000 operates at a predetermined center frequency based on the capacitive effects of equivalent capacitors C1, C2, and C3. In this embodiment, the center frequency is, for example, 315 MHz, which matches the operating frequency of a standard anti-theft device for vehicles. Alternatively, in another example, the relative arrangement of the matching element 200 and the radiating element 100 may be adjusted so that the center frequency of the antenna device 1000 can be changed in order to change the equivalent capacitances C1, C2, and C3.

[0025] Figures 4A and 4B show the frequency characteristics of the antenna device 1000. First, refer to Figure 4A, where the frequency characteristics of the antenna device 1000 are shown by the forward reflection coefficient S11 of the antenna device 1000 at different frequencies. In the design of the printed pattern 81 of the antenna device 1000, predetermined equivalent capacitances C1, C2, and C3 can be formed between the radiating element 100 and the ground area 300, based on the relative arrangement of the protruding portions 210, 220, and 230 of the matching element 200 and the radiating element 100, so that the frequency characteristics of the antenna device 1000 meet the specifications required by the user. The embodiment in Figure 4A shows that at a frequency of 315 MHz, the forward reflection coefficient S11 of the antenna device 1000 has a valley (i.e., the minimum value of the forward reflection coefficient S11 is achieved). This indicates that the center frequency of the antenna device 1000 is substantially equal to 315 MHz, which conforms to the specifications for the vehicle anti-theft device required by the user.

[0026] Next, referring to Figure 4B, the relative arrangement of the protruding portions 210, 220, and 230 of the matching element 200 and the radiating element 100 may be changed, thereby adjusting the equivalent capacitances C1, C2, and C3 between the radiating element 100 and the grounded area 300, and thus the center frequency of the antenna device 1000 may change. The embodiment in Figure 4B shows that at a frequency of 433 MHz, the forward reflection coefficient S11 of the antenna device 1000 has a local minimum value. This indicates that the center frequency of the antenna device 1000 has been changed to 433 MHz.

[0027] Based on the above embodiment, the antenna device 1000 of the disclosure can form at least one equivalent capacitor between the radiating element 100 and the ground area 300 by placing a matching element 200 between the radiating element 100 of the printed pattern 81 and the ground area 300. Due to the capacitive effect of the equivalent capacitor, the center frequency of the antenna device 1000 can be adjusted to meet the user's requirements. Compared to conventional helical antennas for vehicle anti-theft devices, the size of the antenna device 1000 of the disclosure is significantly reduced. Furthermore, the antenna device 1000 of the disclosure can be manufactured in a simple manner in the form of a printed antenna, and manufacturing costs can also be significantly reduced.

[0028] It will be apparent to those skilled in the art that various modifications and variations can be made to the disclosed embodiments. The specification and examples are illustrative only, and the true scope of the disclosure is intended to be shown by the appended claims and their equivalents.

Claims

1. An antenna device that operates at a center frequency, wherein the antenna device is A substrate having a first surface, The substrate has a conductive layer disposed on the first surface thereof, The conductive layer has a printed pattern, and the printed pattern is A radiating element having a plurality of meandering portions arranged along a first direction, wherein two adjacent meandering portions are substantially parallel to each other and electrically coupled. Each of the aforementioned meandering sections is A first section extending along a second direction, A second section substantially parallel to the first section, It includes a third section extending along the first direction and electrically coupled to the first section and the second section, A radiating element in which each of the first section, the second section, and the third section has a strip-like shape, and each of the first section, the second section, and the third section forms a "U-turn" shape, A matching element having a plurality of protruding portions arranged along the first direction, wherein any two adjacent protruding portions are substantially parallel to each other and electrically insulated from each other, An antenna device in which each of the protruding portions of the matching element is sandwiched between two adjacent meandering portions of the radiating element along a second direction, and the second direction is not parallel to the first direction.

2. The antenna device according to claim 1, wherein the second direction is substantially orthogonal to the first direction.

3. The antenna device according to claim 1, wherein at least one or more of the meandering portions of the radiating element are sandwiched between two adjacent protruding portions of the matching element along the second direction.

4. The antenna device according to claim 1, wherein each of the protruding portions of the matching element is substantially parallel to the first and second sections of each of the meandering portions of the radiating element and is electrically isolated.

5. The antenna device according to claim 1, wherein the length of each first section of the meandering portion of the radiating element is substantially equal to the length of the second section, and the length of each first section of the meandering portion is longer than the length of each protruding portion of the matching element.

6. Each of the protruding portions of the matching element has a strip-like shape, and each of the protruding portions is The first end of the radiating element that is not sandwiched between two adjacent meandering portions, The second end is located on the opposite side of the first end in the second direction. The antenna device according to claim 1, having the following features.

7. The antenna device according to claim 6, wherein each of the protruding portions of the matching element extends at the second end along the second direction between two adjacent meandering portions of the radiating element.

8. The aforementioned print pattern further, The antenna device according to claim 6, comprising a grounding region that surrounds the radiating element along the first and second directions and is electrically coupled in the first direction to the first end of each of the protruding portions of the matching element.

9. The antenna device according to claim 8, wherein each of the protruding portions of the matching element forms an equivalent capacitance between the radiating element and the grounded region.

10. The antenna device according to claim 9, wherein the antenna device operates at a center frequency based on the equivalent capacitance formed by the protruding portion of the matching element.

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