TWI536672B - Broadband antenna - Google Patents

Description

Broadband antenna

The present invention relates to an antenna, and more particularly to a wideband antenna covering a plurality of system bands.

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 competing to emerge and enter thousands of households. Consumers can enjoy the convenience brought by high-tech anytime and anywhere, making these portable wireless communication devices become an indispensable part of modern people's daily life.

Among these wireless communication devices, an antenna device for transmitting and receiving radio waves to transmit and exchange radio data signals is undoubtedly one of the most important components in a wireless communication device. In recent years, the emergence of various communication systems and their applications has also led to the demand for antennas to be designed for broadband antennas covering multiple system bands. At the same time, the appearance of these wireless communication devices tends to be thinner and smaller, resulting in antenna design. In addition to broadband, there is also a need for miniaturization. How to reduce the size of the antenna and have broadband characteristics has become the biggest challenge for various antenna manufacturers.

In view of this, the present invention provides a wideband antenna that is small in size and can cover multiple system bandwidths.

A broadband antenna includes a first radiator, a second radiator, a connecting portion and a feed line, wherein the first radiator and the second radiator are connected by the connecting portion; the first radiator and the first radiator The two radiators are arranged in parallel, and the first radiator has a rectangular frame structure for adjusting the impedance matching and the application bandwidth of the front end of the broadband antenna, and the second radiator is a symmetric structure, including a plurality of A radiating arm and a plurality of second radiating arms increase the impedance bandwidth by mutual coupling between the arms.

Compared with the prior art, the broadband antenna adopts a double-adjusted impedance matching structure to increase the working bandwidth, high radiation efficiency, small volume, and the wide frequency range can cover the global positioning system (GPS), the mobile phone system ( DCS/PCS/UMTS) and wireless local area networks (WLAN) and other communication systems.

10‧‧‧Broadband antenna

11‧‧‧First radiator

111‧‧‧First long side

113‧‧‧Second long side

115‧‧‧ Short side

13‧‧‧Second radiator

131‧‧‧ first side

1311‧‧‧First Radiation Arm

133‧‧‧ second side

1331‧‧‧second radiation arm

135‧‧‧Connecting edge

15‧‧‧Connecting Department

17‧‧‧Feeding line

30‧‧‧ boards

1 is a perspective view of a broadband antenna disposed on a circuit board in accordance with a preferred embodiment of the present invention.

2 is a main dimension drawing of the wideband antenna shown in FIG. 1.

FIG. 3 is an optimum reflection loss diagram of the broadband antenna shown in FIG. 1. FIG.

4 is a graph showing the radiation efficiency of the wideband antenna shown in FIG. 1.

Referring to FIG. 1, a broadband antenna 10 according to a preferred embodiment of the present invention is disposed on a circuit board 30 in a portable wireless communication device (not shown) such as a mobile phone or a personal digital assistant (PDA). The side is electrically connected to the circuit board 30 for transmitting and receiving radio waves to transmit and exchange radio data signals.

The broadband antenna 10 includes a first radiator 11, a second radiator 13, and a connecting portion. 15 and a feed line 17. The first radiator 13 is connected to the circuit board 30 by a feed line 11 , and the first radiator 11 and the second radiator 13 are connected to each other by a connecting portion 15 .

The first radiator 11 has a planar rectangular frame shape, and includes a first long side 111, a second long side 113, and two short sides 115. The first long side 111 is opposite to the second long side 113, and the two short sides 115 are oppositely disposed. The first long side 111, the second long side 113, and the two short sides 115 have substantially the same width. The impedance matching and the applied bandwidth of the wideband antenna 10 are adjusted by adjusting the lengths of the first long side 111, the second long side 113, and the two short sides 115.

The second radiator 13 is a symmetrical planar frame structure, and includes a first side 131, a second side 133, and a connecting edge 135. The first side edge 131 and the second side edge 133 are oppositely disposed, and have the same shape and are respectively perpendicularly connected to the two ends of the connecting edge 135. The length of the connecting edge 135 is slightly longer than the length of the first long side 111 and the second long side 113 of the first radiator 11 . The first side 131 extends toward the middle of the second side 133 with a plurality of first radiating arms 1311. The plurality of first radiating arms 1311 are disposed at equal intervals from the end of the first side 131 away from the connecting side 135 parallel to the connecting side 135. The first radiating arms 131 are elongated, and in the present embodiment, the number is four. The second side 131 extends a plurality of second radiating arms 1331 at equal intervals toward the first side 133. The second radiating arm 1331 and the first radiating arm 1311 are identical in shape and number, and are disposed at intervals. The symmetrical structure of the second radiator 13 is similar to the dipole antenna, and has the function of adjusting impedance matching and radiating electromagnetic waves. When the number of the first radiation arm 1311 and the second radiation arm 1331 is increased, the finite area is limited. In this case, the coupling between the two can be enhanced to increase the impedance bandwidth.

The first radiator 11 is disposed in parallel with the surface of the second radiator 13 and is connected The surface of the joint 15 is vertically connected. The second radiator 13 is located on one side of the first radiator 11 , and specifically the outer edge of the connecting edge 135 of the second radiator 13 is aligned with the inner edge of the second long side 113 of the first radiator 11 . The connecting portion 15 is perpendicularly connected to the first radiator 11 and the second radiator 13 respectively. The connecting portion 15 is a rectangular plate-like body, one end of which is perpendicularly connected to the middle of the inner edge of the second long side 113 of the first radiator 11 and the other end of which is perpendicularly connected to the second radiator 13 The middle of the outer edge of the edge 135.

One end of the feed line 17 is vertically connected to the middle of the first long side 111 of the first radiator 11 , and the other end is vertically connected to the circuit board 30 , and the feed line 17 , the first radiator 11 and the circuit The plates 30 are located on the same plane.

Referring to FIG. 2, the main dimensions of the broadband antenna 10 of the preferred embodiment are shown. The length of the first long side 111 of the first radiator 11 is 11 mm, and the length of the short side 115 is 2 mm. The length of the first side 131 of the second radiator 13 is 13 mm; the length of the connecting side 135 is 20 mm; the length of the first radiating wall 1311 is 8 mm, the width is 0.5 mm, and the spacing between adjacent first radiating arms 1311 It is 2.5mm.

Please refer to FIG. 3, which is a schematic diagram of an optimized return loss (RL) obtained by the broadband antenna 10 under simulated software detection according to the preferred embodiment. As can be seen from FIG. 3, during the test, the broadband antenna 10 has a high frequency -6 dB reflection loss bandwidth of up to 1300 MHz (1400 MHz to 2700 MHz). Therefore, the bandwidth of the broadband antenna 10 can cover the bandwidth of five communication systems such as GPS 1500 MHz, DCS 1800 MHz, PCS 1900 MHz, UMT S2100 MHz, and WLAN 2400 MHz.

Please refer to FIG. 4 , which is a schematic diagram showing the radiation efficiency of the operating frequency band of the broadband antenna 10 measured by the analog software in the preferred embodiment. As can be seen from Figure 4, the broadband day Line 10 has an average radiation efficiency of more than 90% in its working frequency band, and has stable radiation performance and application value.

Compared with the prior art, the broadband antenna 10 adopts a double-adjusted impedance matching structure to increase the working bandwidth, high radiation efficiency, small volume, and the wide frequency range can cover communication systems such as GPS, DCS/PCS/UMTS and WLAN.

In summary, the present invention complies with the requirements of the invention patent and submits a patent application according to law. However, the above-mentioned embodiments are only the embodiments of the present invention, and the scope of the present invention is not limited to the above-described embodiments, and those skilled in the art will be equivalently modified or changed in the spirit of the invention. It is included in the scope of the following patent application.

10‧‧‧Broadband antenna

11‧‧‧First radiator

111‧‧‧First long side

113‧‧‧Second long side

115‧‧‧ Short side

13‧‧‧Second radiator

131‧‧‧ first side

1311‧‧‧First Radiation Arm

133‧‧‧ second side

1331‧‧‧second radiation arm

135‧‧‧Connecting edge

15‧‧‧Connecting Department

17‧‧‧Feeding line

30‧‧‧ boards

Claims (7)

A broadband antenna includes a first radiator, a second radiator, a connecting portion and a feeding line, wherein the first radiator and the second radiator are connected by the connecting portion; the improvement is: the first The radiator is disposed in parallel with the surface of the second radiator. The first radiator has a rectangular frame structure for adjusting impedance matching and application bandwidth of the front end of the broadband antenna, and the second radiator is a symmetric structure. The first side edge, a second side opposite to the first side, a plurality of first radiating arms and a plurality of second radiating arms, the plurality of first radiating arms are oriented by the first side The second side of the second radiating arm extends from the second side toward the first side, and the impedance bandwidth is increased by mutual coupling between the radiating arms. The broadband antenna according to claim 1, wherein the second radiator further includes a connecting edge, and the first side and the second side are the same in size and are respectively connected to the two ends of the connecting side. . The broadband antenna of claim 2, wherein the plurality of first radiating arms are equally spaced from the connecting side from the end of the first side away from the connecting side. The wideband antenna of claim 3, wherein the plurality of first radiating arms are elongated. The broadband antenna of claim 3, wherein the second radiating arm is symmetrically spaced from the first radiating arm, and is equidistant from the second side toward the first side and parallel to the connecting side. Extend it. The broadband antenna of claim 1, wherein the first radiator includes a first long side, a second long side and two short sides, and the first long side and the second long side Relatively disposed, the two short sides are oppositely disposed, by adjusting the lengths of the first long side, the second long side, and the two short sides, To adjust the impedance matching and application bandwidth of the front end of the broadband antenna. The wideband antenna according to claim 6, wherein the first radiator is connected to a circuit board by the feed line, and the three are located on the same plane.