CN100470929C - Low sidelobe dual band and wide band planar endfire antenna - Google Patents

Abstract

A low sidelobe dual-band and wide-band planar endfire antenna comprises a substrate having a first side, a second side opposite to the first side, a first surface and a second surface; the first radiator is arranged on the first surface of the substrate and provided with a first inclined part, a first concave part and a first electrical connection part, and the first inclined part is arranged opposite to the first concave part; the second radiator is arranged on the second surface of the substrate and provided with a second inclined part, a second concave part and a second electrical connection part, the second inclined part is arranged opposite to the second concave part, and the second inclined part is arranged opposite to the first inclined part to form an included angle; the two refraction parts are arranged on the side surfaces of the two sides of the substrate; the conductive element is provided with a conductive body and a grounding conductor, the conductive body is electrically connected with the first electrical connecting part, the grounding conductor is electrically connected with the second electrical connecting part, or the conductive body is electrically connected with the second electrical connecting part, and the grounding conductor is electrically connected with the first electrical connecting part.

Description

Low sidelobe dual-band and broadband planar end-fire antenna

technical field

The invention relates to an end-fire antenna, in particular to a low-side-lobe dual-band and wide-band planar end-fire antenna operable in a dual-frequency environment.

Background technique

The vigorous development of wireless transmission brings various products and technologies applied to multi-frequency transmission, so that many new products have the performance of wireless transmission in order to meet the needs of consumers. The antenna is an important component used to transmit and receive electromagnetic wave energy in the wireless transmission system. Without the antenna, the wireless transmission system will not be able to transmit and receive data. Therefore, the role of the antenna is an indispensable part in wireless transmission. Choosing an appropriate antenna can not only help to combine the appearance of the product and improve the transmission characteristics, but also can further reduce the cost of the product. Due to the fact that the antenna design methods and production materials used in various application products are not the same. In addition, the frequency band required for each country is different, and considerable consideration must be taken when designing the antenna. Currently The more common specifications for frequency bands include IEEE 802.11, and the most popular Bluetooth communication (802.15.1), etc., among which Bluetooth works in the 2.4GHz frequency band, and 802.11 is divided into 802.11a and 802.11b for the 5GHz frequency band and 2.4GHz frequency band respectively. GHz band for definition.

General antennas can be classified into directional antennas (also called traveling wave antennas) and omnidirectional antennas (also called resonant wave antennas). There are many variations of directional antennas, such as patch antennas or end-fire antennas.

An existing directional antenna, as shown in FIG. 1, a patch antenna 10 is arranged on a dielectric substrate 15, and a ground plane 16 and a patch plane 17 are respectively formed on the opposite surfaces, Moreover, the ground plane 16 and the patch plane 17 are formed by a plurality of thin metal sheets with a thickness of millimeters. The side length of patch plane 17 is λ/2 (λ is the wavelength of radio wave). A hole is formed in the middle part of the dielectric substrate 15 , and the core conductor 20 of the coaxial cable 19 passes through the hole and is soldered to the patch plane 17 . A hole 23 is formed on a support substrate 22 , and the coaxial cable 19 is disposed through the hole 23 . In addition, the outer conductor of the coaxial cable 19 is connected to the ground plane 16 . The support substrate 22 is an insulator, and the dielectric component 27 is fixed on the support substrate 22 via the spacers 26 disposed at the corners of the support substrate 22 .

The above-mentioned directional antenna can only operate in a single frequency band, which is not practical for the multi-frequency design of modern technology. In addition, the design of the antenna is precise, but the components of the existing method are relatively complicated. Any error in size or alignment assembly may cause the change of the operating frequency band of the antenna, which is not easy to match, and the complexity of the components will also increase. assembly cost.

Therefore, how to make the directional antenna have a dual-band function, increase the operating bandwidth and reduce the assembly cost, so as to meet the requirements of modern technology and consumers, is one of the current topics.

Contents of the invention

The purpose of the present invention is to overcome the deficiencies and defects of the prior art, and provide a low-sidelobe dual-band and wide-band planar endfire antenna that can increase the operating frequency bandwidth and can be applied to two different frequency bands at the same time.

In order to achieve the above-mentioned purpose, the present invention provides a low-sidelobe dual-band and broadband planar end-fire antenna, including:

A substrate having a first side, a second side opposite to the first side, a first surface and a second surface opposite to the first surface;

A first radiator, disposed on the first surface of the substrate, the first radiator has a first slope, a first recess and a first electrical connection, wherein the first slope and the first a concave portion is provided opposite to each other;

A second radiator, disposed on the second surface of the substrate, the second radiator has a second slope, a second recess and a second electrical connection, wherein the second slope and the first Two recesses are arranged opposite to each other, and the second slope is arranged opposite to the first slope to form an included angle;

a first refraction portion disposed on the first side surface of the substrate; and

a conductive element having an electrical conductor and a ground conductor,

Wherein, the conductor is electrically connected to the first electrical connection part, the ground conductor is electrically connected to the second electrical connection part, or the conductor is electrically connected to the second electrical connection part, and the ground conductor is electrically connected to the second electrical connection part. The first electrical connection part is electrically connected.

Based on the above, because the low-sidelobe dual-band and wide-band planar end-fire antenna of the present invention utilizes the first oblique portion and the second oblique portion which are oppositely arranged to form an included angle, so as to cause the traveling waves of each frequency to radiate in the The specific direction, combined with the setting of the first concave part and the second concave part, enables the end-fire antenna to operate in dual-frequency mode, and the refraction part refracts the side lobes emitted by the end-fire antenna, which can improve the frequency of the main wave The power density of the flap results in a high gain effect.

Description of drawings

FIG. 1 is a schematic diagram showing a conventional patch antenna;

2A and 2B are schematic diagrams showing a low-sidelobe dual-band and broadband planar end-fire antenna according to a preferred embodiment of the present invention;

FIG. 3 is a field-type radiation measurement diagram showing a low-sidelobe dual-band and broadband planar end-fire antenna according to a preferred embodiment of the present invention;

FIG. 4 is a schematic diagram showing a part of the scope of use of the low-sidelobe dual-band and wide-band planar endfire antenna according to a preferred embodiment of the present invention;

FIG. 5 is a measurement diagram showing the application range of the low-sidelobe dual-band and wide-band planar endfire antenna according to a preferred embodiment of the present invention.

Explanation of symbols in the figure

10 patch antenna

15 Dielectric substrate

16 Ground plane

17 SMD plane

19 coaxial cable

22 Supporting substrate

23 holes

26 Dividers

27 Dielectric components

3 Low sidelobe dual-band and broadband planar end-fire antenna

31 Substrate

311 first surface

312 second surface

313 side

313’ the other side

32 The first radiator

321 First slope

322 The first concave part

323 The first electrical connection part

33 Second radiator

331 Second slope

332 Second concave part

333 Second electrical connection part

34 Refraction Department

34’ another refraction part

35 Conductive components

351 Conductor

352 Grounding conductor

41 The first feed point

42 Second feed point

W1 first width

W2 Second width

D1, D2 radius

θ1 included angle

R1 The first radiation pattern diagram

R2 Second Radiation Pattern Diagram

Detailed ways

The low-sidelobe dual-band and wide-band planar endfire antenna according to preferred embodiments of the present invention will be described below with reference to related drawings, wherein the same elements will be described with the same reference symbols.

Please refer to shown in Fig. 2A, the low side lobe double frequency of the preferred embodiment of the present invention and broadband planar end-fire antenna 3, it comprises a substrate 31, a first radiator 32, a second radiator 33, a refraction part 34 and a conductive element 35.

The substrate 31 has a first surface 311 , a second surface 312 opposite to the first surface 311 , and a side surface 313 . The material of the substrate 31 can be a printed circuit board made of BT (Bismaleimide-triazine) resin or FR-4 (Fiberglass reinforced epoxy resin), or it can be made of polyimide (Polyimide) A flexible film substrate (Flexible film substrate), in this embodiment, the material of the substrate 31 is glass fiber reinforced epoxy resin (FR-4).

The first radiator 32 is disposed on the first surface 311 of the substrate 31, and the first radiator 32 has a first inclined portion 321, a first concave portion 322 opposite to the first inclined portion 321, and a first electrical characteristic. Connecting part 323 .

The second radiator 33 is disposed on the second surface 312 of the substrate 31, and the second radiator 33 has a second slope 331, a second recess 332 opposite to the second slope 331, and a second electrical Connecting part 333 . The second inclined portion 331 is disposed opposite to the first inclined portion 321 to form an included angle θ1. In this embodiment, the included angle θ1 is between 20 degrees and 30 degrees. Furthermore, the material of the first radiator 32 and the second radiator 33 can be metal. In this embodiment, the material of the first radiator 32 and the second radiator 33 is copper.

The refraction part 34 is arranged on the side surface 313 of the substrate 31, and it can be arranged on the side surface 313 of the substrate 31 relative to the first concave part 322 (as shown in FIG. 2A ). Please refer to FIG. 2B as shown in this embodiment. Another refraction portion 34 ′ is included, which is disposed on the other side surface 313 ′ of the substrate 31 opposite to the second concave portion 332 . In addition, the material of the refraction portion 34 can be metal. In this embodiment, the material of the refraction portion 34 is copper, which is the same as that of the first radiator 31 and the second radiator 32 .

The refraction part 34 refracts the side lobe of the traveling wave generated by the first concave part 322 and the second concave part 332 to the main lobe to increase the power density of the main lobe. , resulting in a high gain effect. Please refer to FIG. 3, the figure measured before the first radiation pattern diagram R1 is not provided with the refraction part 34, as in the prior art, the figure measured after the second radiation field pattern diagram R2 is provided with the refraction part 34, such as In the technology described in the present invention, it can be observed that part of the side lobe is refracted to the main lobe by the refraction part 34, thereby increasing the power density of the main wave; since the second radiation pattern can be clearly identified from Fig. 3 The side lobe of R2 is lower than the side lobe of the first radiation pattern R1, so the inventors call the present invention a "low side lobe" dual-band and broadband planar end-fire antenna.

The conductive element 35 has a conductor 351 and a grounding conductor 352. The conductor 351 and the grounding conductor 352 are electrically connected to the first electrical connection part 323 and the second electrical connection part 333 respectively. In this embodiment, the conductor 351 and the The first electrical connection part 323 is electrically connected, and the ground conductor 352 is electrically connected to the second electrical connection part 333. In addition, the conductor 351 can also be electrically connected to the second electrical connection part 333, and the ground conductor 352 is electrically connected to the first electrical connection part 333. Connecting portion 323 is electrically connected. In this embodiment, the conductive element 35 can be a coaxial transmission line, wherein the conductor 351 is equivalent to the central wire of the coaxial transmission line, and the ground conductor 352 is equivalent to the ground conductor of the coaxial transmission line. In addition, the connection method between the conductive element 35 and the first radiator 32 and the second radiator 33 can be changed according to the shape of the applied product, and it only needs to be based on the connection between the conductor 351 and the ground conductor 352 and the first electrical connection part 323 respectively. The principle of electrical connection with the second electrical connection portion 333 is sufficient.

In this embodiment, the first electrical connection part 323 further includes a first feed-in point 41, and the second electrical connection part 333 further includes a second feed-in point 42, the conductor 351 of the conductive element 35 and the ground The conductors 352 are electrically connected to the first feeding point 41 and the second feeding point 42 respectively.

The low-sidelobe dual-band and wide-band planar endfire antenna 3 of the present invention uses the narrow and gradually widening radiation parts formed by the first slope 321 and the second slope 331 to induce traveling waves of various frequencies, and then can be operated in dual For the frequency band, please refer to FIG. 4 , the first width W1 is used to induce the traveling wave of the high frequency band, and the second width W2 is used to induce the traveling wave of the low frequency band. In addition, the radius D1 of the first concave portion 322 is approximately equal to the radius D2 of the second concave portion 332 . In this embodiment, the radius D1 of the first concave portion 322 is about 5 mm to 8 mm.

In this type of end-fire antenna, the larger the width of the radiation part used to induce the traveling wave, the easier it is to operate the antenna in the low frequency band. However, for size considerations, if the width of the radiation part is increased, the end-fire The size of the radio antenna will also increase accordingly, so the present invention utilizes the fine adjustment of the radius D1 of the first concave portion 322 and the radius D2 of the second concave portion 332 for impedance matching, so that the antenna can operate in high frequency band and low frequency band at the same time. Please refer to FIG. 5 , wherein the vertical axis represents the voltage static standing wave ratio (VSWR), and the horizontal axis represents the frequency (Frequency). The generally acceptable voltage static standing wave ratio is about 2, and under the definition of less than 2, in this embodiment, the low-sidelobe dual-band and broadband planar end-fire antenna can operate in the frequency band of about 2.4GHz and about 5GHz, That is, it can cover the frequency bands used by most countries.

To sum up, the low-sidelobe dual-band and wide-band planar endfire antenna of the present invention utilizes the first slope and the second slope that are oppositely arranged to form an included angle, so as to induce the traveling waves of each frequency to radiate in a specific direction , combined with the first concave portion and the second concave portion as an impedance match so that the end-fire antenna can cover the low-frequency part (such as 2.4GHz in this embodiment) to operate in a dual-frequency mode, plus the refraction portion, the end-fire The side lobe emitted by the antenna is refracted to the main lobe, and the power density of the main lobe is increased to result in a high gain effect. Compared with the prior art, the present invention utilizes simpler elements to make the directional antenna, so the assembly cost is lower than the cost of the existing method, and the antenna can be operated in dual-frequency mode with a smaller volume. The effect of large bandwidth enables a wide range of applications and can also meet the needs of consumers.

The above description is for illustration only, not for limitation. Any equivalent modification or change without departing from the spirit and scope of the present invention shall be included in the scope of the claims.

Claims (11)

1. A low-sidelobe dual-band and broadband planar end-fire antenna, characterized in that it comprises: A substrate having a first side, a second side opposite to the first side, a first surface and a second surface opposite to the first surface; A first radiator, disposed on the first surface of the substrate, the first radiator has a first slope, a first recess and a first electrical connection, wherein the first slope and the first a concave portion is provided opposite to each other; A second radiator, disposed on the second surface of the substrate, the second radiator has a second slope, a second recess and a second electrical connection, wherein the second slope and the first Two recesses are arranged opposite to each other, and the second slope is arranged opposite to the first slope to form an included angle; a first refraction portion disposed on the first side surface of the substrate; and a conductive element having an electrical conductor and a ground conductor, Wherein, the conductor is electrically connected to the first electrical connection part, the ground conductor is electrically connected to the second electrical connection part, or the conductor is electrically connected to the second electrical connection part, and the ground conductor is electrically connected to the second electrical connection part. The first electrical connection part is electrically connected. 2. The low-sidelobe dual-band and broadband planar endfire antenna as claimed in claim 1, wherein the first refracting portion is disposed on the first side surface of the substrate opposite to the first concave portion. 3. The low-sidelobe dual-band and wide-band planar end-fire antenna as claimed in claim 2, wherein, further comprising: A second refraction portion is disposed on a second side surface of the substrate opposite to the second concave portion. 4. The low-sidelobe dual-band and broadband planar endfire antenna as claimed in claim 1, wherein the angle formed by the first slope and the second slope is between 20 degrees and 30 degrees. 5. The low-sidelobe dual-band and broadband planar endfire antenna as claimed in claim 1, wherein the radius of the first recess is equal to the radius of the second recess, wherein the radius of the first recess is 5 mm to 8 mm. between millimeters. 6. The low-sidelobe dual-band and wide-band planar endfire antenna as claimed in claim 1, which is operable in the 2.4GHz frequency band and the 5GHz frequency band. 7. The low-sidelobe dual-band and broadband planar endfire antenna as claimed in claim 1, wherein the first radiator and the second radiator are made of metal. 8. The low-sidelobe dual-band and wide-band planar endfire antenna as claimed in claim 1, wherein the refraction portion is made of metal. 9. The low-sidelobe dual-band and broadband planar endfire antenna as claimed in claim 1, wherein the conductive element is a coaxial transmission line. 10. The low-sidelobe dual-band and wide-band planar endfire antenna according to claim 1, wherein the substrate is made of glass fiber reinforced epoxy resin. 11. The low-sidelobe dual-band and broadband planar end-fire antenna as claimed in claim 1, further comprising: a first feed-in point arranged on the first electrical connection part; and a second feed-in point, set on the second electrical connection part, The first feed point is electrically connected to the conductor of the conductive element, the second feed point is electrically connected to the ground conductor of the conductive element, or the first feed point is electrically connected to the ground conductor of the conductive element connected, the second feeding point is electrically connected to the conductor of the conductive element.

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