TWI524595B - Antenna - Google Patents

Description

antenna

This case is about an antenna technology, especially related to a multi-frequency antenna.

With the advancement of communication technology, electronic devices and their wireless application functions have become more widely used. For example, electronic products such as 3G smart phones and personal digital assistants (PDAs) frequently appear in daily life. In particular, the integration and application of various antennas greatly enhances the convenience of life by providing wireless communication functions that are fast and not restricted by physical lines.

However, under the thinner and lighter design of the mobile communication device, the design space and the clearance space are getting smaller and smaller, but the operating frequency band required is more and more, and the efficiency and radiation field of the antenna must be considered in the same fashion. To maintain good communication quality. For the design of the antenna, it is undoubtedly a considerable challenge.

The present invention provides an antenna comprising: a feed end, a ground end, a ring metal portion, and a protruding metal portion. The ground terminal is electrically connected to the ground plane. Loop The metal portion extends from the feed end to the ground end, and the turns form a loop antenna structure. The protruding metal portion is electrically connected to the metal part of the ring, and the distance between the protruding metal portion and the ground end is shorter than the distance between the protruding metal portion and the feeding end, and the protruding metal portion and the metal portion of the ring are formed at the opposite feeding end and the ground end. Planar inverted F antenna structure.

1‧‧‧Antenna

10‧‧‧Circle Metals

100‧‧‧First Radiation Arm

102‧‧‧second radiation arm

104‧‧‧Connecting arm

12‧‧‧Outstanding Metals Department

14‧‧‧ Ground plane

3‧‧‧Antenna

30‧‧‧Circle Metals

32‧‧‧Prominent Metals Department

4‧‧‧Antenna

40‧‧‧Circle Metals

42‧‧‧Outstanding metal department

420‧‧‧Bending

5‧‧‧Antenna

50‧‧‧Circle Metals

500‧‧‧ first part

502‧‧‧ second part

52‧‧‧Outstanding metal department

54‧‧‧Slots

6‧‧‧Antenna

60‧‧‧Circle Metals

600‧‧‧ current zero interval

62‧‧‧Outstanding metal department

64‧‧‧ Ground plane

7‧‧‧Antenna

70‧‧‧Circle Metals

700‧‧‧Coupling components

72‧‧‧Prominent Metals Department

720‧‧‧Coupling components

1 is a plan view of an antenna according to an embodiment of the present invention; FIG. 2 is a diagram showing a relationship between return loss and frequency of the antenna of FIG. 1 according to an embodiment of the present invention; and FIG. 3 is a second embodiment of the present invention. 4 is a top view of the antenna in the third embodiment of the present invention; FIG. 5 is a plan view of the antenna in the fourth embodiment of the present invention; and FIG. 6 is a plan view of the antenna in the fifth embodiment of the present invention; Figure 7 is a plan view of the antenna in the sixth embodiment of the present invention.

Please refer to Figure 1. Figure 1 is a plan view of an antenna 1 in the first embodiment of the present invention. The antenna 1 includes a feed end A, a ground end B, a ring metal portion 10, and a protruding metal portion 12.

The feed terminal A is used to feed a signal, and the ground terminal B is electrically connected to a ground plane 14. The ring metal portion 10 extends from the feed end A to the ground end B to form a loop type antenna structure. In other words, the ring metal part The two endpoints of 10 are feed A and ground B. In the embodiment illustrated in FIG. 1 , the ring metal portion 10 is an L-ring structure and includes a first radiating arm 100 , a second radiating arm 102 , and a connecting arm 104 . The first radiating arm 100 is electrically connected to the feeding end A, the second radiating arm 102 is electrically connected to the grounding end B, and the connecting arm 104 is electrically connected to the first radiating arm 100 and the second radiating arm 102. The first radiating arm 100, the second radiating arm 102, and the connecting arm 104 of the ring metal portion 10 may be separately formed and then electrically connected, or may be integrally formed, which is not limited thereto. .

The protruding metal portion 12 is electrically connected to the ring metal portion 10. In different embodiments, the protruding metal portions 12 may be integrally formed with the ring metal portion 10, or may be electrically connected to each other after being separately formed. The distance between the protruding metal portion 12 and the grounding end B is shorter than the distance between the protruding metal portion 12 and the feeding end A. In the present embodiment, the protruding metal portion 12 is rectangular and formed on the second radiating arm 102 in the ring metal portion 10. Therefore, the protruding metal portion 12 and the ring metal portion 10 are opposite to the feeding end A and the ground end B to form a Planar Inverted F Antenna (PIFA).

Therefore, the antenna 1 will contain two antenna structures at the same time. One of them is a loop-type antenna structure formed by the loop metal portion 10, and the other is a planar inverted-F antenna structure formed by the loop metal portion 10 and the protruding metal portion 12.

Please refer to Figure 2. Fig. 2 is a diagram showing the relationship between the return loss and the frequency of the antenna 1 of Fig. 1 in an embodiment of the present invention. Among them, the horizontal axis is the frequency, the unit is GHz, and the vertical axis is the return loss, the unit is in dB.

As shown in FIGS. 1 and 2, the loop type antenna structure mainly formed by the ring metal portion 10 will generate a low frequency resonance mode and at least A frequency doubling resonance mode is provided to provide a first resonance frequency F1 and a second resonance frequency F2 as shown in FIG. In this embodiment, the second resonant frequency F2 is a multiple of the first resonant frequency F1. The planar inverted-F antenna structure formed by the ring metal portion 10 and the protruding metal portion 12 will generate another high frequency resonant mode, providing a third resonant frequency F3.

The first resonant frequency F1 and the frequency range in the vicinity thereof are the first operating frequency band of the low frequency, and the second resonant frequency F2, the third resonant frequency F3 and the frequency range in the vicinity thereof are regarded as the second operating frequency band of the high frequency. The second resonant frequency F2 and the third resonant frequency F3 may determine the bandwidth of the second operating frequency band. In one embodiment, the antenna 1 applied to a wireless local area network (WLAN) is exemplified, and the first operating frequency band may be 2400 to 2480 MHz, and the second operating frequency band may be 4800 to 5800 MHz. Therefore, by the design of the antenna 1, an operating band having a bandwidth of up to 1 GHz can be formed at a high frequency. It should be noted that the above data is only an example. In other embodiments, the resonant frequency and the frequency band range of the antenna 1 may be determined according to the size design and practical application, and are not limited by the above data.

In one embodiment, the length of the ring metal portion 10 refers to the length extending from the feed end A to the ground end B, and the length is related to the first resonant frequency F1 and the second resonant frequency F2 described above. In another embodiment, the length of the protruding metal portion 12 to the ground end B refers to the length L1 from the end of the protruding metal portion 12 to the ground end B as shown in FIG. 1 , and the length and the third resonant frequency F3 Related.

In an embodiment, the length of the ring metal portion 10 is the first operation. One-half wavelength (λ/2) of the frequency band, and the length of the protruding metal portion 12 to the ground end B is a quarter wavelength (λ/4) to a half wavelength (λ/2) of the second operating band. )between. Therefore, the low frequency resonance mode of the antenna 1 is provided by the ring metal portion 10, and the high frequency resonance mode is multiplied by the ring metal portion 10 (one wavelength of the first operating band or three-half wavelength) And the protruding metal portion 12 is provided.

As previously mentioned, the resonant frequency of the loop metal portion 10 or the protruding metal portion 12 is related to the design of its length. For example, the longer the length is designed, the lower the resonance frequency can be achieved. Further, the impedance matching of the antenna 1 can be adjusted by the size design of the ring metal portion 10 or the protruding metal portion 12.

Therefore, in different embodiments, the aforementioned resonant frequency, the bandwidth of the operating band, and the overall antenna 1 impedance matching and size can be adjusted by the shape, length, area or area of the ring metal portion 10 and the protruding metal portion 12. Set up auxiliary components for a more flexible design.

Please refer to Figure 3. Fig. 3 is a plan view of the antenna 3 in the second embodiment of the present invention. Similar to the embodiment of Fig. 1, the antenna 3 of Fig. 3 includes a feed end A, a ground end B, a ring metal portion 30, and a protruding metal portion 32. Hereinafter, components having differences between FIG. 3 and FIG. 1 will be described, and the same components will not be described again.

In this embodiment, the protruding metal portion 32 is trapezoidal, and the trapezoidal lower bottom is electrically connected to the ring metal portion 30. The length of the protruding metal portion 32 to the ground end B, that is, the length from the top of the trapezoid to the ground end B affects the frequency of the resonance. In addition, compared with Figure 1, the impedance of antenna 1 Matching can be more elastically adjusted by the area of the trapezoid.

Please refer to Figure 4. Fig. 4 is a plan view of the antenna 4 in the third embodiment of the present invention. Similar to the embodiment of Fig. 1, the antenna 4 of Fig. 4 includes a feed end A, a ground end B, a ring metal portion 40, and a protruding metal portion 42. The components that differ between FIG. 4 and FIG. 1 will be described below, and the same components will not be described again.

In the present embodiment, the protruding metal portion 42 includes a bent portion 420. The protruding metal portion 42 can extend the total length and the total area of the ground end B by forming the bent portion 420, thereby achieving the effect of adjusting the resonance frequency and the impedance matching. For example, protruding metal portions 42 disposed in a rectangular shape generally occupy a large lateral space. Thus, the originally laterally stretched portion can be reversely extended by the provision of the bent portion 420, maintaining the same overall length and total area in the smaller lateral space. In various embodiments, the protruding metal portion 42 can increase the number of bends to further reduce the lateral space it occupies, and still achieve a desired resonant frequency and bandwidth requirement.

Please refer to Figure 5. Fig. 5 is a plan view of the antenna 5 in the fourth embodiment of the present invention. Similar to the embodiment of Fig. 1, the antenna 5 of Fig. 5 includes a feed end A, a ground end B, a ring metal portion 50, and a protruding metal portion 52. The components that differ between FIG. 5 and FIG. 1 will be described below, and the same components will not be described again.

In the embodiment, the protruding metal portion 52 is electrically connected with the ring metal portion 50 to form a slit 54. The slot 54 separates the ring metal portion 50 into the first portion 500 and the second portion 502. The first portion 500 and the second portion 502 are electrically connected through the protruding metal portion 52. Pick up. Under this design, the length of the loop metal portion 50 will be substantially equal to the total length of the first portion 500, the second portion 502, and the projecting metal portion 52. Therefore, by obtaining an additional length by the protruding metal portion 52, the ring metal portion 50 will have a more elastic selection in the length design of the first portion 500 or the second portion 502 to conform to the resonant frequency and frequency. Wide demand.

Please refer to Figure 6. Fig. 6 is a plan view of the antenna 6 in the fifth embodiment of the present invention. Similar to the embodiment of Fig. 1, the antenna 6 of Fig. 6 includes a feed end A, a ground end B, a ring metal portion 60, and a protruding metal portion 62. The components that differ between FIG. 6 and FIG. 1 will be described below, and the same components will not be described again.

In the present embodiment, the ring metal portion 60 further includes a Current Null Region 600. The current zero point interval 600 is the position in the ring metal portion 60 where the current is the smallest. In one embodiment, the current zero interval 600 is located approximately half of the length of the ring metal portion 60. The area of the current zero interval 600 can be used to determine the resonant frequency of the loop antenna structure formed by the loop metal portion 60. For example, when the area of the current zero interval 600 is designed to be larger, the resonance frequency can be shifted to the low frequency, and the size of the area can also assist in adjusting the impedance matching of the antenna 1 at the same time.

In another embodiment, the distance L2 between the current zero interval 600 and the ground plane 64 determines the coupling capacitance formed by the current zero interval 600 and the ground plane 64, thereby adjusting the resonant frequency of the ring metal portion 60. For example, when the distance between the current zero point interval 600 and the ground plane 64 is smaller than the L2 design, the coupling capacitance formed by the current zero point interval 600 and the ground plane 64 is larger, so that the resonance frequency can be lowered. And the size of this spacing L2 can also assist at the same time Adjust the impedance matching of antenna 1.

Please refer to Figure 7. Figure 7 is a plan view of the antenna 7 in the sixth embodiment of the present invention. Similar to the embodiment of Fig. 1, the antenna 7 of Fig. 7 includes a feed end A, a ground end B, a ring metal portion 70, and a protruding metal portion 72. The components that differ between FIG. 7 and FIG. 1 will be described below, and the same components will not be described again.

In the present embodiment, the ring metal portion 70 and the protruding metal portion 72 respectively include coupling elements 700 and 720. Coupling elements 700 and 720 can also provide the ability to adjust the resonant frequency as well as impedance matching. In one embodiment, coupling elements 700 and 720 are chip inductors or wafer capacitors. For example, the coupling elements 700 and 720 are arranged to achieve the effect of reducing the resonant frequency. In various embodiments, the coupling element can also be selectively disposed only on the collar metal portion 70 or only on the protruding metal portion 72.

In different embodiments, the antenna 1 may adopt a combination of the above different design manners, for example, the slot as shown in FIG. 5 and the coupling element as shown in FIG. 7 may be simultaneously formed, or may be simultaneously disposed as shown in FIG. The bent portion is increased in area of the current zero interval as shown in Fig. 6. Therefore, the antenna 1 of the present invention has a more flexible design in the resonance frequency of the antenna 1, the bandwidth of the operating band, the impedance matching, and the size.

It should be noted that in the above embodiment, the ring metal portion 10 is described by taking an L shape as an example. In other embodiments, it may be implemented in a rectangular shape, a circular shape or other different shapes, and is not limited to the above embodiments. Similarly, the protruding metal portion 72 may be implemented, for example, in an L-shape, a U-shape, or a T-shape, or other possible shapes, in addition to the shape described in the above embodiments. The embodiments are limited.

In the case where only the loop type antenna structure is provided, impedance matching is difficult because of its inductive property, and it is difficult to achieve wide-band operation. Therefore, with the protruding metal portion of the antenna of the present invention, not only the impedance matching of the frequency doubling mode of the original loop antenna can be improved, but also the 1/4 wavelength resonant mode of the planar inverted F antenna can be excited, so that the antenna has both antennas. A hybrid design with the advantages of a ring-shaped antenna structure and a planar inverted-F antenna structure. Among them, the antenna structure operating at a low frequency is formed by a ring-shaped antenna structure that is less sensitive to the environment, and is resistant to the coupling of metal components in the surrounding environment, so that the required antenna clearance area can be reduced. The high frequency operating band is provided by the frequency doubling resonance mode of the loop antenna structure and the resonant mode of the planar inverted F antenna structure to achieve wide frequency operation. Therefore, the antenna of the present case can meet the requirements of the operating band of the dual-frequency and wide-band of the wireless local area network system.

The present disclosure has been disclosed in the above embodiments, but it is not intended to limit the disclosure. Any one skilled in the art can make various changes and modifications without departing from the scope of the disclosure. The scope of protection is subject to the definition of the scope of the patent application.

1‧‧‧Antenna

10‧‧‧Circle Metals

100‧‧‧First Radiation Arm

102‧‧‧second radiation arm

104‧‧‧Connecting arm

12‧‧‧Outstanding Metals Department

14‧‧‧ Ground plane

Claims (14)

An antenna includes: a feeding end; a grounding end, wherein the grounding end is electrically connected to a grounding surface; a ring metal portion extending from the feeding end to the grounding end to form a loop-shaped antenna structure; And a protruding metal portion electrically connected to the metal portion of the ring, wherein a distance between the protruding metal portion and the ground end is shorter than a distance between the protruding metal portion and the feeding end, wherein the protruding metal portion and the ring The slot of the metal portion of the ring is further formed with a slot, the slot separating the metal portion of the ring into a first portion and a second portion, the first portion and the second portion The parts are electrically connected through the protruding metal portion. The antenna of claim 1, wherein the ring metal portion is an L-ring structure, comprising: a first radiating arm electrically connected to the feeding end; and a second radiating arm electrically connected to The grounding end, wherein the protruding metal portion is formed on the second radiating arm; and a connecting arm electrically connecting the first radiating arm and the second radiating arm. The antenna of claim 1, wherein the protruding metal portion is a rectangle or a trapezoid. The antenna of claim 1, wherein the protruding metal portion includes at least a bent part. The antenna of claim 1, wherein the ring metal portion further comprises a Current Null Region, and an area of the current zero interval determines a resonant frequency of the loop antenna structure and an impedance matching. The antenna of claim 1, wherein the ring metal portion further comprises a current zero interval, and the distance between the current zero interval and the ground plane determines a resonant frequency and an impedance matching of the loop antenna structure. The antenna of claim 1, wherein the ring metal portion further comprises a coupling element. The antenna of claim 7, wherein the coupling element is a chip inductor or a wafer capacitor. The antenna of claim 1, wherein the protruding metal portion further comprises a coupling element. The antenna of claim 9, wherein the coupling element is a chip inductor or a wafer capacitor. The antenna of claim 1, wherein the ring metal portion provides a first operating frequency band, the frequency doubling resonance mode of the ring metal portion, and the protruding metal portion provide a second operating frequency band, wherein the second operation The frequency band is higher than the first Operating frequency band. The antenna of claim 11, wherein the length of the metal portion of the ring is one-half of a wavelength of the first operating band. The antenna of claim 12, wherein the length of the protruding metal portion to the ground is between a quarter wavelength and a half wavelength of the second operating band. The antenna of claim 1, wherein the protruding metal portion and the ring metal form a planar inverted-F antenna with respect to the feeding end and the ground.