TWI832117B - Single-fed dual-polarized patch antenna and sensing system using the same - Google Patents

Abstract

A single-fed dual-polarized patch antenna includes a first single-fed single-polarized antenna, a second single-fed single-polarized antenna, and a power distributor. A first polarized direction of the first single-fed single-polarized antenna is different from a second single polarized direction of the second single-fed single-polarized antenna. An area of the first reflector of the first single-fed single-polarized antenna is equal to an area of the first antenna substrate of the first single-fed single-polarized antenna. An area of the second reflector plate of the second single-fed single-polarized antenna is equal to an area of the second antenna substrate of the second single-fed single-polarized antenna. A first microstrip line and a second microstrip line of the power divider are electrically connected to the first single-fed single-polarized antenna and the second single-fed single-polarized antenna, respectively.

Description

Single-feed dual-polarization flat-panel antenna and sensing system using it

The present invention relates to a flat panel antenna, and in particular to a single-feed dual-polarized flat panel antenna that can be used as a reader antenna in timed sports events and a sensing system using the same.

Timed sports events use radio frequency identification (RFID) systems. The RFID system requires a reader antenna to read the radio frequency tag (usually worn on the uppers of the contestants' shoes) to determine whether the contestants have passed the tag corresponding to the reader antenna. Location. If the reading range of the reader antenna is very small, missed readings may occur, so it is necessary to increase the reading range, that is, to broaden the field pattern.

In addition, in addition to increasing the reading range of the reader antenna to improve the missed read rate, the polarization direction of the reader antenna and the RF tag can also be used to improve the missed read rate. Common reader antennas and radio frequency tags are linearly polarized. The polarization directions of the two must be horizontal (that is, the polarization directions of the two must be the same) to achieve the maximum reading benefit. If the polarization directions of the two are If it is vertical, it will not be read.

Please refer to Figure 1, which is a schematic plan view of a traditional single-feed single-polarization antenna. The traditional single-feed single-polarized antenna 1 includes a single-polarized antenna unit 11, an antenna substrate 12, a reflection plate 13 and a feed line 14. The single polarization antenna unit 11 is formed on the surface of the antenna substrate 12 , and the antenna substrate 12 is disposed above the reflection plate 13 .

Please refer to Figures 1 and 2. Figure 2 is a YZ plane field pattern diagram of a traditional single-feed single-polarized antenna operating at 910 MHz. The area of the reflector 13 of the traditional single-feed single-polarized antenna 1 is larger than the antenna substrate 12, and the XY plane projection of the antenna substrate 12 falls into the XY plane projection of the reflector 13, thereby increasing the gain in the maximum radiation direction. However, this approach results in a narrower field pattern. As shown in Figure 2, when the operating frequency is 910 MHz, the horizontal polarization gains at 90 degrees and 270 degrees are -8.07dB and -9.36dB respectively, while the vertical polarization gains at 90 and 270 degrees are -9.35 respectively. dB and -15.86dB.

Please refer to Figure 3, which is a schematic plan view of a circular Wilkinson power divider. The circular Wilkinson power divider 3 includes a first microstrip line 31 , a second microstrip line 32 , a circular transmission line 33 , a front-end circuit microstrip 34 and a divider substrate 35 . The first microstrip line 31 , the second microstrip transmission line 32 , the circular transmission line 33 and the front-end circuit microstrip line 34 are formed on the surface of the distributor substrate 35 . The first end of the circular transmission line 33 is electrically connected to the first microstrip line 31 , the second end of the circular transmission line 33 is electrically connected to the second microstrip line 32 , and the third end of the circular transmission line 33 It is electrically connected to the front-end circuit microstrip line 34, and the first end and the second end are relative to the third end. The front-end circuit microstrip line 34 is used to electrically connect the front-end circuit, such as a radio frequency signal transceiver, and the first microstrip line 31 and the second microstrip line 32 are respectively used to electrically connect to the antenna. Because the traditional power divider 3 has a circular transmission line 33, the overall area is relatively large. Its length, width and area are 65 mm, 82 mm and 5330 mm2 respectively.

Based on at least one object of the present invention, the present invention provides a single-feed dual-polarized planar antenna, which includes a first single-feed single-polarized antenna, a second single-fed single-polarized antenna, and a power divider. The first polarization direction of the first single feed single polarization antenna is different from the second polarization direction of the second single feed single polarization antenna. The area of the first reflecting plate of the first single-feed single-polarization antenna is equal to the area of the first single-feed single-polarization antenna. The area of the first antenna substrate, and the plane projection of the first reflecting plate falls into or overlaps the plane projection of the first antenna substrate. The area of the second reflection plate of the second single-feed single-polarization antenna is equal to the area of the second antenna substrate of the second single-feed single-polarization antenna, and the planar projection of the second reflection plate falls into or overlaps the second Plane projection of the antenna substrate. The first microstrip line and the second microstrip line of the power divider are electrically connected to the first single-feed single-polarization antenna and the second single-feed single-polarization antenna respectively.

In an embodiment of the invention, the first polarization direction is perpendicular to the second polarization direction.

In an embodiment of the present invention, the single-feed dual-polarization planar antenna further includes a carrier board. The carrier board is used to carry the first single-feed single-polarization antenna, the second single-feed single-polarization antenna and the power splitter thereon.

In an embodiment of the present invention, the first single-feed single-polarized antenna includes a first single-polarized antenna unit, a first antenna substrate, a first reflector and a first feed line. The first antenna substrate is used to form the first single polarization antenna unit on one surface thereof. The first reflecting plate is used for disposing the first antenna substrate thereon. The first feed line is electrically connected to the first single polarization antenna unit and the first microstrip line.

In an embodiment of the present invention, the first single-polarized antenna unit is implemented by one radiator, or is implemented by stacking multiple radiators.

In an embodiment of the present invention, the second single-feed single-polarization antenna includes a second single-polarization antenna unit, a second antenna substrate, a second reflection plate, and a second feed line. The second antenna substrate is used to form a second single-polarized antenna unit on one surface thereof. The second reflective plate is used for disposing the second antenna substrate thereon. The second feed line is electrically connected to the second single polarization antenna unit and the second microstrip line.

In an embodiment of the present invention, the second single-polarized antenna unit is implemented by one radiator, or is implemented by stacking multiple radiators.

In an embodiment of the present invention, the power divider includes a divider substrate, a first microstrip line, a second microstrip line, a rectangular transmission line and a front-end microstrip line. The first microstrip line, the second microstrip line, the front-end microstrip line and the rectangular transmission line are formed on the surface of the distributor substrate. The rectangular transmission line has a first end and a second end that are adjacent and opposite to each other, and has a third end that is opposite to the first end and the second end, wherein the first end and the second end are electrically connected to the first microstrip line respectively. and a second microstrip line, and a third end electrically connected to the front-end circuit microstrip line.

Based on at least one object of the present invention, the present invention provides a sensing system, which includes any of the aforementioned single-feed dual-polarized flat panel antennas and a radio frequency signal transceiver. The RF signal transceiver is electrically connected to the single-feed dual-polarized flat panel antenna, and is used to transmit the RF signal to the RF tag through the single-feed dual-polarized flat-panel antenna, and receive the sensor of the RF tag through the single-fed dual-polarized flat panel antenna. The sensing signal is used to sense the radio frequency tag by the sensing system.

In an embodiment of the invention, the sensing system further includes a recording device. The recording device is used to record the sensing signal and the sensing time point at which the sensing signal is acquired.

According to the above, the above-mentioned single-feed dual-polarization planar antenna and the sensing system using the same have a lower missed reading rate, a smaller antenna area, and a wider reading range.

1: Traditional single feed single polarization antenna

11:Single polarized antenna unit

12:Antenna substrate

13: Reflective plate

14:Feeding line

3: Traditional power divider

31: The first microstrip line

32: Second microstrip line

33: Circular transmission line

34: Front-end circuit microstrip line

35:Distributor base plate

4: Single feed single polarization antenna

41:Single polarization antenna unit

42:Antenna substrate

43: Reflective plate

44:Feeding line

6:Power divider

61: The first microstrip line

62: Second microstrip line

63: Circular transmission line

64: Front-end circuit microstrip line

65:Distributor base plate

7: Single feed dual polarization flat panel antenna

71: Carrier board

8: Sensing system

81:RF signal transceiver

82:Recording device

9:RF tag

Figure 1 is a schematic plan view of a traditional single-feed single-polarized antenna.

Figure 2 is a YZ plane field pattern diagram of a traditional single-feed single-polarized antenna operating at 910 MHz.

Figure 3 is a schematic plan view of a circular power divider.

FIG. 4 is a schematic plan view of a single-feed single-polarization antenna according to an embodiment of the present invention.

FIG. 5 is a YZ plane field pattern diagram of a single-feed single-polarized antenna operating at 910 MHz according to an embodiment of the present invention.

Figure 6 is a schematic plan view of a power divider according to an embodiment of the present invention.

FIG. 7 is a schematic plan view of a single-feed dual-polarization planar antenna according to an embodiment of the present invention.

Figure 8 is a block diagram of a sensing system for a timed competition according to an embodiment of the present invention.

In order to help the examiner understand the technical features, content, advantages and effects of the present invention, the present invention is described in detail below in conjunction with the accompanying drawings and in the form of embodiments. The drawings used are only for illustration. and auxiliary instructions are not necessarily the actual proportions and precise configurations after implementation of the present invention. Therefore, the proportions and configuration relationships of the attached drawings should not be interpreted to limit the scope of rights of the present invention in actual implementation. It is stated in advance. .

Please refer to Figures 4, 6 and 7. Figure 4 is a schematic plan view of a single-feed single-polarization antenna according to an embodiment of the present invention. Figure 6 is a schematic plan view of a power divider according to an embodiment of the present invention. Figure 7 is a schematic plan view of a power divider according to an embodiment of the present invention. A schematic plan view of a single-feed dual-polarized flat panel antenna according to an embodiment of the invention. The single-feed dual-polarized flat panel antenna 7 is used in sensing systems and can be used as a reader antenna. The single-feed dual-polarized flat panel antenna 7 includes two single-feed single-polarized antennas 4 (the left and right single-feed single-polarized antennas 4 ), a power divider 6 and a carrier board 71 . The carrier board 71 is used to carry two single-feed single-polarization antennas 4 and the power splitter 6 thereon. The first microstrip line 61 and the second microstrip line 62 of the power divider 6 are electrically connected to the left and right single-feed single-polarized antennas 4 through the feed lines 44 of the left and right single-feed single-polarized antennas 4 respectively. 4. The two reflection plates 42 respectively corresponding to the left and right single-feed single-polarization antennas 4 are spaced apart from each other and are two independent reflection plates.

In order to allow any radio frequency tag worn on the upper of the shoe to be effectively sensed by the single-feed dual-polarization flat-panel antenna 7, the polarization direction of the single-feed single-polarized antenna 4 on the left is matched with the single-feed single-polarized antenna 4 on the right. The polarization directions of the polarized antennas 4 are designed in different directions, and preferably, the polarization direction of the single-feed single-polarized antenna 4 on the left is perpendicular to the polarization direction of the single-feed single-polarized antenna 4 on the right.

In addition, in order to broaden the field pattern close to the ground, the area of the reflection plate 42 of each single-feed single-polarized antenna 4 and the area of the antenna substrate 43 of the single-polarized antenna 4 are designed to be the same as each other, and let The reflection plate 42 and the antenna substrate 43 are arranged in alignment with each other. That is, although the antenna substrate 43 is disposed on the reflection plate 42, the XY plane projections of the two overlap and are aligned with each other. In other words, the present invention is designed so that the XY plane projection of the reflection plate 42 falls within and does not exceed the XY plane projection of the antenna substrate 43 , that is, the area of the reflection plate 42 is equal to the area of the antenna substrate 43 .

In addition, the single-polarized antenna unit 41 of the above-mentioned single-polarized antenna 4 can be realized by a single piece of radiator, or it can be realized by stacking multiple microstrip patches with radiators. In short, the present invention does not use single-polarization. The implementation of antenna unit 41 is considered a limitation.

Please further refer to FIG. 4 and FIG. 5 simultaneously. FIG. 5 is a YZ plane field pattern diagram of a single-feed single-polarization antenna operating at 910 MHz according to an embodiment of the present invention. The single-feed single-polarization antenna 4 includes a single-polarization antenna unit 41 , an antenna substrate 42 , a reflection plate 43 and a feed line 44 . The antenna substrate 42 is used to allow the single polarized antenna unit 41 to be formed on one surface thereof. The reflecting plate 43 is used for the antenna substrate 42 to be disposed thereon. The feed line 44 is electrically connected to the single polarization antenna unit 41 .

In order to make the field pattern close to the ground widen and increase the reading range, so that the radio frequency tags for subsequent sports events can be worn on the shoe surface at will, and a good reading effect will also be achieved. As mentioned above, the antenna substrate 42 and The XY plane projections of the reflecting plates 43 overlap each other and are aligned with each other. As shown in Figure 5, when the operating frequency is At 910 MHz, the horizontal polarization gains at 90 degrees and 270 degrees are -5.90dB and -5.95dB respectively, while the vertical polarization gains at 90 and 270 degrees are -20.42dB and -13.26dB respectively.

Please refer to Figure 6. In order to reduce the area of the power divider 6, the power divider 6 is designed as follows. The power divider 6 includes a divider substrate 65 , a first microstrip line 61 , a second microstrip line 62 , a rectangular transmission line 63 and a front-end circuit microstrip line 64 . The first microstrip line 61 , the second microstrip line 62 , the front-end circuit microstrip line 64 and the rectangular transmission line 63 are formed on the surface of the distributor substrate 65 . The rectangular transmission line 63 has a first end and a second end that are adjacent and opposite to each other, and has a third end that is opposite to the first end and the second end, wherein the first end and the second end are electrically connected to the first microstrip respectively. The line 61, the second microstrip line 62, and the third end are electrically connected to the front-end circuit microstrip line 64. Since the power divider 6 is designed to have a rectangular transmission line 63, the overall area can be reduced, with its length, width and area being 63 mm, 70 mm and 4410 mm2 respectively.

Please refer next to FIG. 8 , which is a block diagram of a sensing system for a timed competition according to an embodiment of the present invention. The sensing system 8 includes the aforementioned single-feed dual-polarization planar antenna 7 , a radio frequency signal transceiver 81 and a recording device 82 . The radio frequency signal transceiver 81 is electrically connected to the single-feed dual-polarized flat panel antenna 7 and is used to transmit the radio frequency signal to the radio frequency tag 9 through the single-feed dual-polarized flat panel antenna 7 and through the single-fed dual-polarized flat panel antenna 7 The sensing signal of the radio frequency tag is received, thereby allowing the sensing system 8 to sense the radio frequency tag 9 . The recording device 82 is electrically connected to the radio frequency signal transceiver 81 and is used to record the sensing signal and obtain the sensing time point of the sensing signal.

In addition, in other embodiments, the recording device 82 can be removed, and instead, the measurement system 8 is signal-connected to an external electronic device, and transmits the sensing signal and the sensing time point at which the sensing signal is obtained to the external electronic device for recording.

Based on the above, the single-feed dual-polarized flat-panel antenna according to the embodiment of the present invention can have a good reading effect when the radio frequency tag is perpendicular or parallel to it, allowing contestants to place the radio frequency tag on the antenna. It can be worn on the upper of the shoe in any way (preferably, it is still recommended to place it in either a horizontal or vertical way), and it can reduce the rate of missed readings. Furthermore, compared with the dual-polarized flat panel antenna formed by a traditional single-fed single-polarized antenna and a circular power divider, the single-fed dual-polarized flat-panel antenna according to the embodiment of the present invention can have a smaller area. and size, which is conducive to the manufacturing of miniaturized products.

To sum up, the single-feed dual-polarization planar antenna and the sensing system using the same provided by the embodiments of the present invention can accurately achieve the expected use effects, and the present invention has not been disclosed before the application. Fully comply with the provisions and requirements of patent law. If you apply for an invention patent in accordance with the law, I sincerely request you to review it and grant a patent, which will be very beneficial. However, the above-mentioned illustrations and descriptions are only preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Generally, those familiar with the art may make other modifications based on the characteristic scope of the present invention. Equivalent changes or modifications should be considered as not departing from the design scope of the present invention.

7: Single feed dual polarization flat panel antenna

71: Carrier board

6:Power divider

4: Single feed single polarization antenna

44:Feeding line

Claims (9)

A single-fed dual-polarized flat panel antenna, including: a first single-fed single-polarized antenna and a second single-fed single-polarized antenna, wherein a first pole of the first single-fed single-polarized antenna The polarization direction is different from a second polarization direction of the second single-fed single-polarized antenna, and an area of a first reflector of the first single-fed single-polarized antenna is equal to the first single-fed single-polarized antenna. An area of a first antenna substrate of the antenna, a planar projection of the first reflecting plate falls into or overlaps a planar projection of the first antenna substrate, and a planar projection of the second single-feed single-polarization antenna An area of the second reflective plate is equal to the area of a second antenna substrate of the second single-feed single-polarization antenna, and a planar projection of the second reflective plate falls into or overlaps with the second antenna substrate. a planar projection; and a power divider, a first microstrip line and a second microstrip line electrically connecting the first single-feed single-polarized antenna and the second single-feed single-polarized antenna respectively; There is a distance between the first reflecting plate and the second reflecting plate, so that the first reflecting plate and the second reflecting plate are two independent reflecting plates; wherein the power divider includes: a divider substrate; the third A microstrip line and the second microstrip line are formed on a surface of the distributor substrate; a front-end circuit microstrip line is formed on the surface of the distributor substrate; and a rectangular transmission line is formed on the distributor The surface of the substrate has a first end and a second end that are adjacent and opposite to each other, and has a third end that is opposite to the first end and the second end; wherein the first end and the second end are respectively The first microstrip line and the second microstrip line are electrically connected, and the third end is electrically connected to the front-end circuit microstrip line. The single-feed dual-polarization planar antenna as claimed in claim 1, wherein the first polarization direction is perpendicular to the second polarization direction. The single-feed dual-polarization planar antenna as claimed in claim 1 further includes: a carrier board for carrying the first single-feed single-polarization antenna, the second single-feed single-polarization antenna and the power Distributor on it. The single-feed dual-polarization planar antenna according to claim 1, wherein the first single-feed single-polarization antenna includes: a first single-polarization antenna unit; the first antenna substrate is used to allow the The first single-polarized antenna unit is formed on one surface thereof; the first reflecting plate is used to allow the first antenna substrate to be disposed thereon; and a first feed line is electrically connected to the first single-polarized antenna. unit with this first microstrip line. The single-feed dual-polarized planar antenna as claimed in claim 4, wherein the first single-polarized antenna unit is implemented by one radiator, or is implemented by stacking multiple radiators. The single-feed dual-polarization planar antenna as claimed in claim 1, wherein the second single-feed single-polarization antenna includes: a second single-polarization antenna unit; and the second antenna substrate is used to allow the The second single-polarized antenna unit is formed on one surface thereof; the second reflective plate is used to allow the second antenna substrate to be disposed thereon; and a second feed line is electrically connected to the second single-polarized antenna. unit with this second microstrip line. The single-feed dual-polarization planar antenna as claimed in claim 6, wherein the second single-polarization antenna unit is implemented by one radiator, or by stacking multiple radiators. A sensing system, including: a single-feed dual-polarization flat-panel antenna as described in one of claims 1-7; a radio frequency signal transceiver electrically connected to the single-feed dual-polarization flat-panel antenna to A radio frequency signal is transmitted to a radio frequency tag through the single-feed dual-polarized flat panel antenna, and a sensing signal of the radio-frequency tag is received through the single-fed dual-polarized flat panel antenna, thereby allowing the sensing system to be used Sense the radio frequency tag. The sensing system of claim 8 further includes: a recording device for recording the sensing signal and a sensing time point at which the sensing signal is acquired.

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