TWI473348B - Multiband antenna and wireless communication device using the same - Google Patents

Description

Multi-frequency antenna and wireless communication device using the multi-frequency antenna

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

With the rapid development of wireless communication technology and information processing technology and the increasing living standards of people, mobile wireless communication devices such as mobile phones and personal digital assistants (PDAs) are emerging. With the popularity of wireless communication devices, its SAR (Specific Absorption Rate) quality is a performance indicator that may directly affect the health of users of wireless communication devices, and is gradually receiving attention and attention. In general, the SAR value of the wireless communication device should be minimized before the performance of the existing wireless communication device is reduced. In order to ensure the health of users, some countries have established the highest standards for SAR, such as the US standard of 1.6W / kg, the European standard of 2.0W / kg. Since the antenna is the main component of the radiated electromagnetic wave in the wireless communication device, how to improve the structure of the designed antenna is particularly necessary to maintain the radiation efficiency while minimizing the SAR value.

In view of this, it is necessary to provide a multi-frequency antenna that can reduce the SAR value.

In addition, it is necessary to provide a wireless communication device using the above multi-frequency antenna

A multi-frequency antenna includes an antenna carrier and a first antenna portion and a second antenna portion disposed on the antenna carrier, the antenna carrier including a first surface and a second parallel to the first surface The first antenna portion and the second antenna portion are respectively disposed on the first surface and the second surface, and the first antenna portion includes one main radiating portion, a first bent portion and a feed The second antenna portion includes a primary radiation portion and a second curved portion connected in sequence; the primary radiation portion is disposed on the first surface, and the secondary radiation portion is disposed on the second surface, the feeding portion and the second tortuous portion Located in the same plane and perpendicular to the first surface and the second surface.

A wireless communication device includes a printed circuit board and a multi-frequency antenna connected to the printed circuit board; the multi-frequency antenna includes an antenna carrier and a first antenna portion and a second portion disposed on the antenna carrier The antenna carrier includes a first surface and a second surface opposite to the first surface, and the first antenna portion and the second antenna portion are respectively disposed on the first surface and the second surface, The first antenna portion includes one main radiating portion, a first bent portion and a feeding portion; the second antenna portion includes a primary radiating portion and a second bent portion connected in sequence; the main radiating portion is disposed The first radiating portion is disposed on the second surface, and the feeding portion and the second bent portion are located on the same plane and perpendicular to the first surface and the second surface.

Compared with the prior art, when the multi-frequency antenna of the present invention works, the first antenna portion and the second antenna portion disposed in different planes excite a plurality of working frequency bands, and the effective dispersion is caused by excessive current concentration. SAR, the goal of reducing the SAR value.

100‧‧‧Multi-frequency antenna

10‧‧‧First antenna unit

11‧‧‧Main Radiation Department

111‧‧‧Rectangular frame

1111‧‧‧First long side

1112‧‧‧First short side

1113‧‧‧ openings

1114‧‧‧Slit

12‧‧‧First zigzag

121‧‧‧Connecting end

122‧‧‧First zigzag

1221‧‧‧Piece

1222‧‧‧Connector

13‧‧‧Feeding Department

20‧‧‧second antenna unit

21‧‧ ‧ Department of Radiation

211‧‧‧ Subject

2111‧‧‧Second long side

2112‧‧‧Second short side

2113‧‧‧ incision

212‧‧‧Extension

22‧‧‧ Second zigzag

221‧‧‧Substrate

222‧‧‧second zigzag

200‧‧‧Antenna carrier

201‧‧‧ first surface

202‧‧‧ second surface

1 is a schematic diagram of a multi-frequency antenna according to a preferred embodiment of the present invention installed on a wireless communication device.

2 is another embodiment of the multi-frequency antenna of the preferred embodiment of the present invention installed on a wireless communication device A schematic diagram of a perspective.

3 is a diagram showing main dimensions of a first antenna portion of a multi-frequency antenna according to a preferred embodiment of the present invention in an unfolded state.

4 is a diagram showing main dimensions of a second antenna portion of a multi-frequency antenna according to a preferred embodiment of the present invention in an unfolded state.

FIG. 5 is a schematic diagram of return loss (RL) of a multi-frequency antenna according to a preferred embodiment of the present invention.

Referring to FIG. 1 and FIG. 2, the multi-frequency antenna 100 of the preferred embodiment of the present invention includes a first antenna portion 10 and a second antenna portion 20. The first antenna portion 10 and the second antenna portion 20 are mounted on one of the antenna carriers 200 in the wireless communication device, and are located in different planes, and the first antenna portion 10 and the second antenna portion 20 are simultaneously disposed. They are respectively connected to a signal feeding end (not shown) on the printed circuit board in the wireless communication device and a ground terminal (not shown).

The antenna carrier 200 is substantially in the shape of a rectangular parallelepiped and is made of an insulating material. The antenna carrier 200 includes a horizontal first surface 201 and a second surface 202 that is parallel to the first surface 201. The first antenna portion 10 is disposed on the first surface 201, and the second antenna portion 20 is disposed on the second surface 202.

The first antenna portion 10 includes one main radiating portion 11, a first bent portion 12, and a feeding portion 13 which are sequentially connected. The main radiating portion 11 is formed by splicing two symmetrically arranged rectangular frames 111. Each of the rectangular frames 111 includes two opposite first long sides 1111 and two first short sides 1112 connected to the first long sides 1111. An opening 1113 is defined in one of the first long side 1111 and the adjacent first short side 1112. The two rectangular frames 111 are joined together by being connected to the first short side 1112 of the opening 1113. And a slit 1114 is formed between the first long side 1111 having the opening 1113.

The first meandering portion 12 includes a connecting end 121 and a first meandering section 122 connected to the connecting end 121. The connecting end 121 is formed by a splicing of the two first short sides 1112 extending a distance perpendicular to the two first short sides 1112. The connecting end 121 is connected to the first meandering section 122 away from one end of the first short side 1112. The first meandering section 122 is substantially U-shaped, and is formed by two strip-shaped pieces 1221 arranged in parallel and a connecting body 1222 perpendicularly connected to the two pieces 1221. The two ends 1221 are connected to the connecting end 121 and the feeding portion 13 away from one end of the connecting body 1222. The first meandering portion 12 is located in the same plane as the main radiating portion 11.

The feeding portion 13 is a rectangular body that is connected to one end of the body 1221 away from the connecting body 1222. The plane of the feeding portion 13 is perpendicular to the plane of the main radiating portion 11 and the first meandering portion 12.

The second antenna portion 20 includes a primary radiating portion 21 and a second meandering portion 22 connected to the secondary radiating portion 21. The radiation portion 21 includes a main body 211 and an extended end 212. The outer contour of the main body 211 is substantially a rectangular frame, and includes a second long side 2111 disposed opposite to each other and a second short side 2112 disposed opposite to the second long side 2111. One of the second long sides 2111 defines a slit 2113 at an intermediate position. The extending end 212 is formed by a side of the slit 2113 extending in a direction perpendicular to the second long side 2111, and is connected to the second meandering portion 22 away from one end of the secondary radiating portion 21.

The second meandering portion 22 includes a long strip-shaped substrate 221 and two second meandering segments 222 connected to the substrate 221 and symmetrically distributed on both sides of the substrate 221 . The second meandering segments 222 extend from the two ends of the substrate 221 to the two sides of the substrate 221 in a direction perpendicular to the substrate 221, and then extend back to the substrate 221 in a direction parallel to the substrate 221. In the middle position, and folded again to extend perpendicular to the direction of the substrate 221 The segment distance is formed. The end of one of the second meandering segments 222 is perpendicularly connected to the secondary radiating portion 21; the end of the other second meandering segment 222 is connected to the circuit board, and the plane of the entire second meandering portion 22 and the plane of the secondary radiating portion 21 are vertical.

Referring to FIG. 3 and FIG. 4 together, the preferred size of one of the multi-frequency antennas 100 in this embodiment can be determined through experiments. The length of the first short side 1112 of the first antenna portion 10 adjacent to the opening 1113 is equal to the length of the second long side 2111 of the second antenna portion 20, both being 19.2 mm; and the first long side 1111 The length is 11.5 mm, which is slightly larger than the length of the second short side 2112 by 9 mm. When the multi-frequency antenna 100 is installed, first, the first antenna unit 10 and the second antenna unit 20 are placed on the antenna carrier 200 in the wireless communication device, and the main radiating portion 11 of the first antenna portion 10 is set. On the first surface 201 of the antenna carrier 200, and the outer edge of the first short side 1112 adjacent to the opening 1113 is flush with the edge of the first surface 201; the secondary radiating portion 21 of the second antenna portion 20 is disposed on The second surface 202 of the antenna carrier 200, and the outer edge of the second long side 2111 is flush with the edge of the second surface 202; thereby bringing the first short side 1112 adjacent to the opening 1113 and the second having the slit 2113 The long sides 2113 are aligned, and the first meandering portion 12 and the second meandering portion 22 are in the same plane and perpendicular to the plane of the main radiating portion 11 and the secondary radiating portion 21; then, the feeding portion 13 is connected to the printed circuit board. The signal feed end of the upper signal is connected to the ground end of the printed circuit board on the end of the second meandering section 222 of the feed portion 13. When the multi-frequency antenna 100 performs signal radiation, the first antenna portion 10 and the second antenna portion 20 are in different planes, effectively dispersing the SAR caused by excessive current concentration, and achieving the purpose of reducing the SAR value.

Referring to FIG. 5, a schematic diagram of the return loss obtained by the multi-frequency antenna 100 under analog software detection is shown. As can be seen from FIG. 5, during the test, the multi-frequency antenna 100 reduces the SAR value at a phase near a complex operating frequency of 0.9 GHz, 2.4 GHz, and the like. Off indicators and meet antenna design requirements.

100‧‧‧Multi-frequency antenna

10‧‧‧First antenna unit

11‧‧‧Main Radiation Department

111‧‧‧Rectangular frame

1111‧‧‧First long side

1112‧‧‧First short side

1113‧‧‧ openings

1114‧‧‧Slit

12‧‧‧First zigzag

121‧‧‧Connecting end

122‧‧‧First zigzag

1221‧‧‧ tablets

1222‧‧‧Connector

13‧‧‧Feeding Department

20‧‧‧second antenna unit

21‧‧ ‧ Department of Radiation

211‧‧‧ Subject

212‧‧‧Extension

22‧‧‧ Second zigzag

221‧‧‧Substrate

222‧‧‧second zigzag

200‧‧‧Antenna carrier

201‧‧‧ first surface

202‧‧‧ second surface

Claims (6)

A multi-frequency antenna includes an antenna carrier and a first antenna portion and a second antenna portion disposed on the antenna carrier, wherein the antenna carrier includes a first surface and a first surface The first antenna portion and the second antenna portion are respectively disposed on the first surface and the second surface, and the first antenna portion includes one main radiating portion and a first zigzag And a feeding portion; the second antenna portion includes a primary radiating portion and a second bent portion connected in sequence; the main radiating portion is disposed on the first surface, and the secondary radiating portion is disposed on the second surface, the feeding portion and The second meandering portion is located on the same plane and perpendicular to the first surface and the second surface, and the second meandering portion comprises a substrate and two second meandering segments connected to the substrate and symmetrically distributed on both sides of the substrate. The multi-frequency antenna according to claim 1, wherein the main radiating portion is formed by splicing two rectangular frames, each rectangular frame comprising two oppositely disposed first long sides and connected to the second long sides The second short side is opposite to the first short side, and one of the first long side is open to the first short side of the adjacent first short side; the two rectangular frames are connected by the first short side of the second opening The splicing is integrated, and a slit is formed between the first long sides having the openings. The multi-frequency antenna of claim 1, wherein the first meandering portion comprises a connecting end and a first meandering portion, the connecting end is connected to the main radiating portion, and the other end is twisted with the first The first zigzag segment includes two parallel-connected sheets and a connecting body connected to the two-piece body, and the two-piece body is connected to the connecting end and the feeding portion away from one end of the connecting body. The multi-frequency antenna of claim 1, wherein the sub-radiation portion comprises a main body and an extending end, the outer contour of the main body is a rectangular frame, and the second long side of the opposite side is disposed The second long side is connected with the second short side of the opposite side, wherein the second long side is middle A slit is formed at the inter position, and the extending end is formed at a direction perpendicular to the second long side at the slit. The multi-frequency antenna according to claim 1, wherein each of the second meandering segments is extended to a distance parallel to the base by extending opposite ends of the substrate from a direction perpendicular to the substrate. The sheet direction extends to the intermediate position of the substrate and is again folded to extend a distance perpendicular to the substrate to form a distance. A wireless communication device comprising a printed circuit board and a multi-frequency antenna connected to the printed circuit board; wherein the multi-frequency antenna is the multi-frequency antenna according to any one of claims 1 to 5.