TWI536663B - Dual band antenna and wireless communication device using the same - Google Patents

Description

Dual-frequency antenna and wireless communication device using the same

The present invention relates to an antenna, and more particularly to a dual frequency antenna and a wireless communication device using the same.

In wireless communication devices such as mobile phones and personal digital assistants (PDAs), the antenna is the most important component of the wireless communication device as its component for transmitting and receiving radio waves to transmit and exchange radio signals. One. At present, wireless communication devices generally need to have the function of communicating in dual frequency band or more frequency bands, so antenna devices generally use dual-frequency or multi-frequency antennas.

Referring to FIG. 1, a conventional dual-frequency antenna 80 includes a first radiating arm 82 and a second radiating arm 84. The first radiating arm 82 and the second radiating arm 84 are each a long strip structure and are respectively used. Send and receive wireless signals of different frequencies. Generally, when the lengths of the two are respectively set to 1/4 of the wavelength corresponding to the signal to be transmitted and received, a better radiation effect can be obtained. Thus, when the dual-frequency antenna 80 is used to transmit and receive low-frequency signals with long wavelengths, it is often necessary to increase the size of the first radiating arm 82 and the second radiating arm 84. However, the space occupied by the dual-band antenna 80 is too large, which is disadvantageous for reducing the size of the wireless communication device and reducing the development cost.

In view of this, it is necessary to provide a dual-frequency antenna that is small in size and low in design cost.

A dual-frequency antenna includes a first radiator, a second radiator, a feed end, and a ground. The dual-frequency antenna is an inverted-F antenna, and the first radiator and the second radiator The feed end and the ground end are all flat plate structure, the first radiator is connected to the second radiator and located in the same plane, and the feeding end and the ground end are located in another plane and are vertically connected. In the first radiator.

A wireless communication device includes a base body and a dual-frequency antenna, wherein the base body is provided with a grounding point and a signal feeding point, and the grounding point and the signal feeding point are electrically connected to the dual-frequency antenna. The dual-frequency antenna includes a first radiator, a second radiator, a feed end, and a ground. The dual-frequency antenna is an inverted-F antenna, and the first radiator, the second radiator, and the feed The end and the ground end are both flat body structures, the first radiator is connected to the second radiator and located in the same plane, and the feeding end and the ground end are located in another plane and are vertically connected to the first Radiation body.

Compared with the prior art, the first radiator and the second radiator described in the present invention are flat sheets and are disposed in the same plane, thereby effectively solving the installation of the dual-frequency antenna in the prior art. The problem of larger space is conducive to the miniaturization of the wireless communication device and the reduction of the design and development cost of the antenna.

100‧‧‧Double frequency antenna

12‧‧‧First radiator

124‧‧‧Second extension

142‧‧‧First connection segment

20‧‧‧ Grounding

50‧‧‧ base

54‧‧‧ top surface

80‧‧‧Double frequency antenna

84‧‧‧second radiation arm

10‧‧‧Antenna body

122‧‧‧First extension

14‧‧‧Second radiator

144‧‧‧Second connection

30‧‧‧Feeding end

52‧‧‧ end face

56‧‧‧ side

82‧‧‧First Radiation Arm

200‧‧‧Mobile Phone

1 is a schematic structural view of a conventional dual-frequency antenna; FIG. 2 is a schematic diagram of a dual-frequency antenna according to a preferred embodiment of the present invention installed on a base of a wireless communication device; FIG. 3 is a dual-frequency antenna according to a preferred embodiment of the present invention; Stereoscopic view 4 is a perspective view of a wireless communication device in accordance with a preferred embodiment of the present invention.

2 and 3 show a dual-band antenna 100 according to a preferred embodiment of the present invention, which can be applied to a wireless communication device such as a mobile phone or a PDA. In the present embodiment, a dual-frequency antenna 100 applied to the mobile phone 200 (see FIG. 4) will be described as an example. The dual frequency antenna 100 is disposed on a base 50 of the mobile phone 200. The base 50 can be part of a Printed Circuit Board (PCB) of the mobile phone 200.

The base body 50 is substantially a rectangular parallelepiped, and includes an end surface 52, a top surface 54 and a side surface 56. The end surface 52, the top surface 54 and the side surface 56 are disposed perpendicularly to each other. The side surface 56 can be provided with a grounding point (not shown) and a signal feeding point (not shown) according to the prior art. The grounding point is electrically connected to the base 50 and provides grounding for the base 50. The signal feed point is electrically connected to the base 50 and provides signal feeding to the base 50.

The dual-frequency antenna 100 is a Planar Inverted-F Antenna (PIFA). The dual-frequency antenna 100 includes an antenna body 10 , a grounding end 20 , and a feeding end 30 . The grounding end 20 and the feeding end 30 are electrically connected to the antenna body 10 .

The antenna body 10 includes a first radiator 12 and a second radiator 14 . The first radiator 12 and the second radiator 14 are flat metal foil or conductive material coating, both of which are located in the same plane and are attached to the top surface 54 of the base 50, thereby reducing the dual frequency. The installation space required for the antenna 100 is installed, and the dual-frequency antenna 100 is properly supported and protected.

The first radiator 12 is substantially in an "L" shape and is attached to the top surface 54 in parallel. The first radiator 12 includes a first extension 122 and a second extension 124. One end of the first extending portion 122 coincides with an edge of the top surface 54 abutting the end surface 52, and the other end extends away from the end surface 52, and one side of the first extending portion 122 coincides with an edge of the top surface 54 adjacent to the side surface 56. . The second extension 124 is perpendicularly connected to one end of the first extension 122 away from the end 52 and extends away from the side surface 56 to form a rectangle having a length smaller than the first extension 122 and a width corresponding to the first extension 122.

The second radiator 14 includes a first connecting portion 142 and a second connecting portion 144 which are both in a rectangular shape, and the edges of the first connecting portion 142 are on the same straight line from the edge of the side surface 56, and the width of the first connecting portion 142 is larger than the second connecting portion. 144 width. One side of the first connecting section 142 is connected to the first extending section 122, and the adjacent side coincides with the edge of the top surface 54 abutting the end surface 52. One end of the second connecting portion 144 is connected to one side of the first connecting portion 142 away from the end surface 52, and the other end extends in a direction parallel to the first extending portion 122, and the length thereof is slightly smaller than the first connecting portion 142. In the actual process, the width of the second connecting section 144 is generally equal to the width of the first extending section 122 and the distance between the second connecting section 144 and the first extending section 122, correspondingly width of the first connecting section 142. It is set to be about twice the width of the second connecting section 144.

The ground terminal 20 is a flat sheet of metal or a coating of conductive material that is attached to the side 56 in parallel. One end of the grounding end 20 is perpendicularly connected to the first extending section 122, and the other end extends away from the top surface 54, and one side of the grounding end 20 coincides with an edge of the end surface 52 adjacent to the side surface 56. The width of the grounding end 20 is the same as the width of the first extending portion 122, and the length is consistent with the thickness of the base 50. The grounding terminal 20 can be electrically connected to a grounding point disposed on the base 50 to provide grounding for the dual-frequency antenna 100.

The feed end 30 is a flat sheet of metal or a coating of electrically conductive material that is attached to the side 56 in parallel. One end of the feed end 30 is perpendicular to one end of the connection first extension 122 near the ground end 20, and the other end extends in a direction parallel to the ground end 20. The width of the feed end 30 is the same as the width of the first extension 122, and the length is consistent with the ground end 20, and the feed end 30 can be electrically connected to the signal feed point disposed on the base 50 to be the dual frequency. Antenna 100 provides signal feed.

It can be understood that the material of the antenna body 10 can be selected from copper, silver, conductive ink, etc., which can be formed on the substrate 50 by technical means such as etching or plating.

It is experimentally determined that the preferred size of one of the dual-frequency antennas 100 in this embodiment is as follows: the widths of the first extension 122, the second extension 124, and the second connection segment 144 are both set to about 1 mm, and the lengths are respectively set to about 20 mm. 2mm and 3mm. The width of the first connecting section 142 is set to be about 2 mm and the length is set to be about 4 mm. The length and width of the grounding end 20 and the feeding end 30 are respectively set to be about 6 mm and 1 mm, and the distance between the grounding end 20 and the feeding end 30 is set to be about 2 mm.

When the dual-frequency antenna 100 is in operation, after the signal enters from the feeding end 30, a first current path and a second current path having different electrical lengths are respectively formed, and the first current path is from the feeding end 20 Flowing through the first extension 122 to the second extension 124; the second current path flows from the feed end 20 through the first connection section 142 to the second connection section 144. When the first current path and the second current path are respectively proportional to the wavelength of the signals of the two different frequencies (the length of the path is 1/4 wavelength), the first radiator 12 and the second radiator 14 The two signals can be received/transmitted separately, so the invention can operate in two different frequency bands. It can be obtained from the above design dimensions that in the embodiment, the first current path length is about 29 mm, and the resonant frequency range of the first radiator is about 2.4 GHz-2.5 GHz, which satisfies the Bluetooth. (Bluetooth) signal frequency communication requirements; the second current path length is about 13 mm, and the second radiator 14 has a resonance frequency range of about 5.4 GHz to 5.9 GHz. Therefore, the dual-band antenna 100 of the present invention has better effects when transmitting and receiving signals of WIRELESS LAN IEEE 802.11a/b/g/n, WLAN, and the like.

The gain of the antenna (Gain) is the ratio of the power density of the signal generated by the actual antenna and the ideal radiating element at the same point in space under the condition of equal input power. It quantitatively describes the extent to which an antenna concentrates the input power. Referring to Table 1, it is experimentally determined that the maximum gain of the dual-band antenna 100 shown in the preferred embodiment of the present invention varies with the operating frequency. The dual-band antenna 100 conforms to the design requirements of the antenna.

The dual-frequency antenna 100 adopts a planar structure and is attached to the base 50 as a whole. The volume is small, so that the dual-band antenna 100 does not occupy the mechanism configuration space in the mobile phone 200, which is advantageous for thinning the mobile phone 200. . The dual-band antenna 100 has a low cost and can generate a plurality of resonant frequencies during operation, which increases the bandwidth of the dual-band antenna 100, so that the bandwidth of the dual-band antenna 100 can cover multiple communication systems.

In summary, the present invention complies with the requirements of the invention patent and submits a patent application according to law. The above is only the preferred embodiment of the present invention, and the scope of the present invention is not limited to the above-described embodiments, and equivalent modifications or variations made by those skilled in the art in accordance with the spirit of the present invention are It should be covered by the following patent application.

100‧‧‧Double frequency antenna

20‧‧‧ Grounding

50‧‧‧ base

54‧‧‧ top surface

10‧‧‧Antenna body

30‧‧‧Feeding end

52‧‧‧ end face

56‧‧‧ side

Claims (8)

A dual-frequency antenna includes a first radiator, a second radiator, a feed end, and a ground. The improvement is that the dual-frequency antenna is an inverted-F antenna, and the first radiator, The second radiator, the feed end and the ground end are all flat plate structures, the first radiator is connected to the second radiator and located in the same plane, and the feeding end and the ground end are located in another plane. And being vertically connected to the first radiator, wherein the first radiator has an "L" shape, and includes a first extension and a second extension, the second extension being perpendicular to the first extension At one end, the second radiator includes a first connecting section and a second connecting section. The first connecting section has a rectangular shape, and adjacent sides thereof are respectively connected to the first extending section and the second connecting section. The dual-frequency antenna according to claim 1, wherein the dual-frequency antenna obtains a first operating frequency from the first radiator, and the first operating frequency is between 2.4 and 2.5 GHz. The dual-frequency antenna according to claim 1, wherein the dual-frequency antenna obtains a second operating frequency from the second radiator, and the second operating frequency is between 5.7 and 5.9 GHz. The dual-frequency antenna of claim 1, wherein the dual-frequency antenna is made of a metal sheet or a conductive material coating. A wireless communication device includes a base body and a dual-frequency antenna, wherein the base body is provided with a grounding point and a signal feeding point, and the grounding point and the signal feeding point are electrically connected to the dual-frequency antenna, and the improved The dual-frequency antenna is the dual-frequency antenna according to any one of claims 1 to 4. The wireless communication device of claim 5, wherein the substrate is a printed circuit board of a wireless communication device. The wireless communication device of claim 5, wherein the base body comprises one end surface, a top surface and a side surface of the two vertical connections, wherein the first radiator and the second radiator are attached to On the top surface, the feeding end and the grounding end are attached to the side surface, and the feeding end and the grounding end are both in length consistent with the thickness of the base body. The wireless communication device of claim 7, wherein one side of the first radiator overlaps an edge of the abutting side of the top surface; and one side of the second radiator is adjacent to an edge of the top surface coincide.