TWI276251B - High-gain omnidirectional planar monopole antenna - Google Patents

Abstract

The present invention is related to a high-gain omnidirectional planar monopole antenna and mainly comprises a ground plane, a radiating metal line, and a feeding coaxial line. The ground plane is substantially of a rectangular shape. The radiating metal line is composed of a first metal line, a second metal line, and a third metal line. The first metal line has a length of about 0.25 wavelength of the antenna's central operating frequency and is with a distance of less than 3 mm to the ground plane. The second metal line has a length of about 0.5 wavelength of the antenna's central operating frequency and is in the form of a meandered line, whose two ends are connected to the first and third metal lines, respectively. The third metal line has a length of about 0.5 wavelength of the antenna's central operating frequency. The feeding coaxial line is for signal transmission. The present invention is suitable for application in the 2.4 GHz WLAN band for providing high-gain omnidirectional radiation characteristics.

Description

1276251 V. INSTRUCTION DESCRIPTION OF THE INVENTION (1) Technical Field to Which the Invention A Special Invention The present invention relates to a high gain omnidirectional planar monopole antenna which is an antenna applied to a wireless communication product. 'Previous technology】 With the rapid development of the wireless communication industry, the demand for various wireless communication functions has gradually increased. In the case of green-free regional networks and sil products, in order to increase the range of services for communication, the design of bridge antennas with high standards and applications is becoming more and more important. At the same time, a f^^l to a syllabus should also be considered to simplify the structure and production side: Cheng, currently: know the application of the wireless antenna network bridge antenna and monopole antenna as the main figure 'as shown in Figure 7' ^, mostly in the even-line structure, which has an omnidirectional radiation field type but the wave 'sees the dipole day dBi, and it has a more complex antenna junction, and increases only about 2. 2 529783" Dipole antenna design ", Kui, into the dipole antenna of the Republic of China patent, which is a plane 蛀 ^ ^ is not an improved fixed characteristic but the gain of this antenna has a difference in center frequency and bandwidth stability In the present invention, the gain of the egg antenna is not too large for the monopole antenna design, and the I has a local gain omnidirectional flat nAr t sub-line not only the umbrella; ε; e reduces the cost, and its structure Simple, embossed, printed on a dielectric substrate, and has omnidirectionality and high gain, etc. As described above, the unidirectional and omnidirectional radiation monopole antenna of the present invention aims to provide a It has better high-intensity reception quality. ',,' its gain can be 4 · 4 dBi, made

1276251 V. INSTRUCTION DESCRIPTION (2) Another object of the present invention is to provide a monopole antenna having high gain and omnidirectional radiation, and the antenna has a simple structure and can be easily formed on a dielectric substrate by printing or etching techniques. The invention is formed on a dielectric substrate. As can be seen from the above, the antenna structure of the present invention mainly comprises: a ground plane, a round metal wire and a feed coaxial transmission line. The ground plane is substantially rectangular in shape and has a grounding point thereon. The radiant metal wire mainly includes: a first sub-metal wire extending substantially in a straight line shape away from the ground plane, and having a length substantially equal to a 1/4 wavelength of the central operating frequency of the antenna, having a first end point and a second end point relative to the first end point, and having an antenna feed point at the first end point, the first creep and the ground plane having a gap of less than 3 mm; The second sub-metal line, 'having a starting point and an end point, the length from the starting point to the end point is approximately 丨/2 wavelength of the center operating frequency of the antenna, and the starting point and the point have 3 More than a second bend, so that the second sub-wire; shape = two to attack the bent shape, the starting point is connected to the two end points of the first sub-metal line; a third sub-metal line, roughly a straight line shape, the long sound ^ is 1/2 wavelength of the center operating frequency of the antenna, and is substantially the same as the first sub-gold & = extension direction, and one end of the third sub-metal line is connected, : the end point of the second sub-metal line. The feed coaxial transmission line, the ::- center conductor, the line, the antenna connected to the first sub-metal line = ", an outer ground conductor, connected to the ground point of the ground plane, we can borrow Adjusting the radiant metal wire: making the length of the first m sub-metal wire and the third sub-metal wire

Page 8 12762251 V. Description of the invention (3) The current of the first sub-metal wire and the third sub-metal wire is bent to form a reverse current pair on the recursive curve line and the design of the third sub-metal wire The gain value of the antenna can be the length of the line, and the size of the ground plane can be changed and the width of the antenna can be obtained to obtain the antenna of the present invention. Embodiment] Line Gold The metal wire has the same direction of current, and the opposite. At the same time, the shape of the second sub-metal can be effectively suppressed by the shape of the second sub-metal. Thus, the combined radiation of the same current can cause Huang Sheng L to greet the center operating frequency of the antenna; by adjusting the line of the first sub-metal line of the incident metal wire, good impedance matching and impedance bandwidth. Designed for wireless local area network 2. 4

1 is an embodiment of an antenna of the present invention. In this embodiment, the antenna structure includes a ground plane 1 and a radiating metal line 12 and a feed coaxial transmission line 16. In the first embodiment, the grounding surface 丨丨' has a substantially rectangular shape, and has a grounding point 1丨丨, and a radiating metal line 12 is disposed on the grounding surface ,. The line 1 2 can be divided into a first sub-metal line 13 , a second sub-metal line 丨 4 and a third sub-metal line 15 ; wherein the first sub-metal line 13 is substantially in a straight line shape, located at the ground plane 11 The grounding point 111 side extends in a direction away from the grounding plane ,, and has a length substantially equal to 1/4 of the center operating frequency of the antenna, and has a first end point 1 3 1 at one end thereof and a relative to the a second end point 1 3 2 of the first end point 1 3 1 and an antenna feed point 1 3 3 at the first end point 1 3 1 , the first end point 13 3 丨 being located on the ground plane 11 side And between the ground plane and the ground plane 形成 form a less than 3 mm

Page 9 1276251

V. Description of the Invention (4) A second sub-metal wire 14 has a starting point 1 41 and an end point. The starting point 1 4 1 to the end point 1 4 2 is approximately 1 / 2 of the center frequency of the antenna. a wavelength 'and a gap d between the starting point 1 41 and the end point 1 4 2; 142, the degree of operation is approximately 1/2 wavelength of the center operating frequency of the antenna, and has a bend of more than 3 times with the first sub- Folding, the second sub-metal wire 14 is formed into a meandering shape 'the starting point 1 4 1 and connected to the second end point 1 3 2 of the first sub-metal wire 3; a third sub- The metal wire 15 is substantially in the shape of a straight line, and the extending direction of the long metal wire 13 is substantially the same, and the end point of the third sub-metal wire 丨5 is connected to the end point 1 of the second sub-metal wire 14 4 2.

The feed coaxial transmission line 16 includes a center conductor 161 and an outer ground conductor 162. The center conductor 161 is connected to the antenna feed point 1 3 3 of the first sub-metal line 13; the outer layer The grounding conductor 1 6 2 is connected to the grounding point 111 of the grounding surface 11; in the first embodiment, the grounding surface 11 and the radiating metal line 12 can be formed on the dielectric substrate 17 by printing or etching techniques. 2 is a return loss experimental measurement result of one embodiment of the antenna of the present invention. The test parameters we selected are: 1. The ground plane 11 has a length of about 20 fflin and a width of about 10 mm; The first sub-metal wire 13 has a length of about 30 mm and a width of about 3 mm;

The gap between the first end point 1 3 1 of the first sub-metal line 13 and the crucible ground is about 1 mm; the second sub-metal line 14 has a length of about 98 mm and a width of about 5的玻璃纤维基板。 The third sub-metal wire 15 having a length of about 50 mm and a width of about 1 mm; 6 - a glass fiber substrate having a dielectric constant of 4.4.

Page 10 1276251 V. INSTRUCTIONS (5) From the experimental results obtained, under the definition of 10 dB return loss, the impedance of the antenna operating mode is 100 MHz, which can cover the wireless local area network ', ( 2400 -2484 MHz) Operating band. Fig. 3 is a measurement result of the radiation field shape of the antenna of Embodiment 1 of the antenna of the present invention at 2442 MHz. From the experimental results obtained, the antenna has an omnidirectional radiation field pattern in the x_y plane with a gain of 4.4 dBi. Fig. 4 is a graph showing the result of antenna gain measurement of Embodiment 1 of the antenna of the present invention. From the results obtained, the antenna gain in the operational mode is approximately 4. i — 4 · 4 dB 1, which satisfies the gain requirements of the general 2 · 4 GHz wireless local area network operation. 5 is another embodiment 5 of the antenna of the present invention. In the embodiment 5, the structure of the antenna includes a dielectric substrate 57, a radiating metal wire Μ and a microstrip transmission line 56. The dielectric substrate 57 has a first surface 572; the light-emitting metal, the line 52 is located on the first surface 57 1 of the dielectric substrate π, the + έ 姑 姑 姑 金属 金属 及 及 及 及 及 及 及 及 、 、 、 、 The second W is substantially ϊυ, the 1/4 wavelength of the first sub-metal line rate, and the second end point 532 of the first end point 531 of the antenna center operating frequency is present at each of the open ends. - & sub-point H ^ with respect to the starting point 541 and a point 54? buckle the first sub-wire 54 with a female silk rabbit; 、, " point 542 the starting point 541 to the end point 542 The length is approximately the right q ^t wavelength between the antenna center operating frequency & length and the end point 542, and the starting point 541 line 54 forms the second endpoint ml' ° point of the inter-bend metal line 53 And connected to the first 'to the second sub-metal line 5 5 is substantially one

Page 11 1276221 V. Description of the invention (6) One ~-- linear shape, the length is approximately 1/2 wavelength of the center operating frequency of the antenna, and is substantially the same as the extending direction of the first sub-metal wire 5 3 One end 551 of one of the three sub-metal wires 55 is connected to the second sub-metal wire 5 = the service point 5 42. The microstrip transmission line 56 mainly includes a metal line 560 and a ground plane 516. The metal line 516 is located on the first surface 57 1 of the dielectric substrate 57 and is connected to the line end. The first end of the first sub-metal line 53 is located in a portion of the second surface 572 of the dielectric substrate 57, and the portion of the portion corresponds to the first surface 571. The section only contains the metal line 5 6 1 . In the fifth embodiment, the radiation metal line 52 and the microstrip transmission layer 5 6 may be formed on the dielectric substrate 57 by a 4 printing or a registration technique. In the present embodiment 5, the antenna is fed by a micro V transmission line 56, and other structures are the same as those in the first embodiment. Figure 6 is another embodiment 6 of the antenna of the present invention. In this embodiment 6, the structure of the antenna includes a radiating metal line 62 and a coplanar waveguide transmission line 66. The radiant metal line 6 2 further includes a first sub-metal line 63, a second sub-metal line 64, and a third sub-metal line 65. The first sub-metal line 63 is substantially in a straight line shape and length. Roughly 1 / 4 wavelength of the antenna operating frequency, having a first end point 6 3 两端 at each end and a second end point 632 relative to the first point 631; the second sub Line 64 ® has a starting point 6 4 1 and an ending point 6 4 2, and the length from the starting point 6 4 2 to the end point 6 4 2 is approximately the i / 2 wavelength of the antenna operating frequency of the antenna, and the starting point There is more than three bends between the 641 and the end point 642, so that the second sub-metal wire 64 forms a meandering shape, and the starting point is connected to

Page 12 1276251

5. Description of the Invention (7) The second end point 632 of the first sub-metal line 63; the third sub-metal line 65 is substantially in a straight line shape, and the length is approximately 1/2 wavelength of the center operating frequency of the antenna. And the extension direction of the first sub-metal line 63 is substantially the same, the end point 6 5 1 of the third sub-metal line 65 is connected to the end point 6 4 2 of the second sub-metal line 6 4; The planar waveguide transmission line 6 6 further includes a center metal line 6 6 1 , a first ground plane 6 6 2 and a second ground plane 6 6 3 ; wherein the center metal line 6 6 1 is in a straight line shape and is connected to the The first end surface 631 of the first sub-metal line 63; the shape of the first ground plane 66 2 is substantially a rectangle, located on one side of the center metal line 616, and the /

The first ground plane 6 6 2 corresponds to the length of the center metal line 6 6 1 ; the first ground plane 6 63 is also substantially rectangular in shape, corresponding to the first ground plane and corresponding to the center. The other side of the metal line 6 6 1 , and the second ground plane 6 6 3 also corresponds to the center metal line 6 6 i. In the embodiment 6, the antenna is fed by the -coplanar waveguide transmission line 66 The second length is the same as in the first embodiment. In summary, the antenna of the present invention has a simple structure, a low manufacturing cost, and a clear function. The antenna of the present invention has a high industrial application value and is sufficient to conform to the invention. The embodiments described in the above description are merely illustrative of the principles and their effects, and are not intended to limit the invention. Because you can not violate the invention's sleeves, P, +, give, this technology people T j you le « ah God to the upper embodiment. The rights of the present invention are as described in the patent application scope of the following description.

Page 13 1276251 Brief Description of the Drawings Fig. 1 is a structural view showing an embodiment of a monopole antenna of the present invention. Figure 2 is a graph showing the return loss measurement of an embodiment of the antenna of the present invention. Figure 3 is a measurement result of the radiation field type of an embodiment of the antenna of the present invention. Figure 4 is a graph showing the antenna gain measurement results of an embodiment of the antenna of the present invention. Fig. 5 is a structural view showing another embodiment of the antenna of the present invention. Figure 6 is a block diagram showing another embodiment of the antenna of the present invention. Figure 7 is a structural diagram of a dipole antenna of the prior art [Description of main components] 1 - a monopole antenna of the present invention is implemented 5 - a monopole antenna of the present invention is another 6 - a monopole antenna of the present invention 5 1,5 6 2 - Ground plane 1 2,5 2,6 2 -Light metal wire 1 3 1,5 3 1,6 3 1 -First end point 1 3 3 - Antenna feed point 141,541, 641- starting point 1 5, 5 5, 6 5-third sub-metal wire 1, 6, 7 6 - feeding into the same vehicle by transmission line 1 6 2 - outer grounding conductor d - first sub-metal η line first end Point 56 - microstrip transmission line 57, 67 - dielectric substrate 5 7 2 - second surface 66 1 - central metal line example embodiment 111 - ground point 1 3, 5 3, 6 3 - first sub-metal line 1 3 2,5 3 2,6 3 2 -second end point 1 4, 54, 64-second sub-metal line 1 4 2,5 4 2,6 4 2 -end point 151,551,651 -end point 1 6 1 - center conductor 17 - dielectric substrate ^ gap width with ground plane, 5 6 1 - metal line 5 71 - first surface 66 - coplanar waveguide transmission line 6 62 - first ground plane

Page 14 1276251 Brief description of the diagram 6 6 3- Second ground plane 71-Negative 7 - Dipole antenna 7 2 - Positive terminal ❿ 1^· Page 15

Claims (1)

I27625l VI. Patent Application Scope l A high-gain antenna structure consists of a ground plane, the width of the shape, which extends in the direction of a metal of a radiating metal wire, ^ 'at its second end, and the creep point The grounding-second sub-metal end point has a large starting point which is substantially the same as the third sub-metal center operating frequency of the metal line forming the metal line, and the end point of the metal line; and - a feeding coaxial transmission The wire mainly comprises: a center conductor 'connected to the antenna feed point of the first sub-metal line; and an outer ground conductor connected to the ground point of the ground plane. 2. The high-gain omnidirectional planar monopole antenna according to claim 1, wherein the ground plane and the radiating metal line can be printed or etched into an omnidirectional planar monopole antenna, characterized in that: The unipolar shape is substantially a rectangle having a rectangle of less than 2 mm and having a grounding point; 'mainly comprising: a line having a substantially straight line shape facing away from the ground plane and having a length substantially the center operating frequency of the antenna Each of the 1/4 waves has a first end point and an antenna feed point at the first end point relative to the first end point, the first side having a gap of less than 3 mm ;:> Line ' has a starting point and an ending point, the starting point is to 1/2 wavelength of the antenna operating frequency, and there are more than 3 bends between the points, so that the second The sub-turnback bends the shape, and the starting point is connected to the "first sub-two endpoints; and the line is substantially a straight line shape having a length of approximately 1/2 wavelength of the antenna and extending with the first sub-metal line One end of one of the third sub-metal wires Connected to the second sub- Page 16 1276251 VI. Patent Application Formed on a dielectric substrate. The high-gain omnidirectional planar monopole antenna is characterized in that: the monopole antenna structure comprises: a dielectric substrate having a first surface and a second surface; and a radiating metal line on the dielectric substrate The first surface comprises: a first sub-metal line, substantially a straight line shape, having a length substantially equal to a 1/4 wavelength of the antenna operating frequency, having a first end point and a first end opposite to the first end a second end point of the point; a second sub-metal line having a starting point and an end point, the length from the starting point to the end point being approximately 1/2 wavelength of the center operating frequency of the antenna, and the starting point And having a bend of more than 3 times between the end point, such that the second sub-metal wire forms a meandering bent shape, the starting point is connected to the second end point of the first sub-metal wire; The three sub-metal wires are substantially in the shape of a straight line, and have a length substantially equal to a 1/2 wavelength of the central operating frequency of the antenna, and are substantially the same as an extending direction of the first sub-metal wire, and one end of the third sub-metal wire is connected to The second child a microstrip transmission line, and a microstrip transmission line, comprising: a metal line on the first surface of the dielectric substrate and connected to the first end of the first sub-metal line; and a ground plane And a portion of the second surface of the dielectric substrate, and the portion of the portion corresponding to the first surface includes only the metal line. 4. High-gain omnidirectional planar monopole as described in claim 3 Page 17 1276251 6. Patent application line wherein the radiant metal line and the microstrip transmission line can be formed on the dielectric substrate by printing or etching techniques. A high-gain omnidirectional planar monopole antenna is characterized in that: the monopole antenna structure comprises: a radiating metal wire, comprising: a first sub-metal wire, substantially a straight line shape, and the length is substantially The 1/4 wavelength of the antenna operating frequency has a first end point and a second end point relative to the first end point; a second sub-metal line having a starting point and an ending point, the starting point The length to the end point is approximately 1/2 wavelength of the center operating frequency of the antenna, and the bending start point and the end point have more than three bends, so that the second sub-metal line forms a meandering and bending shape. The starting point is connected to the second end of the first sub-metal line; and a third sub-metal line is substantially in a straight line shape having a length of approximately 1/2 wavelength of the antenna center operating frequency, and The extension of the first sub-metal line - . ' is substantially the same, the end of one of the third sub-metal lines is connected to the end of the second sub-metal line; and a coplanar waveguide transmission line, mainly comprising: a center metal line ,for a linear shape connected to the first <end point J of the first sub-metal line, a first ground plane having a shape substantially a rectangle, located at one side of the center metal line, and the first ground plane corresponding to a length of the center metal line; and a second ground plane having a shape substantially a rectangle, located at the center metal line Page 18 1276251 VI. Scope of Application The other side, and the second ground plane corresponds to the length of the center wire. 6. The high gain omnidirectional planar monopole antenna of claim 5, wherein the radiant metal line and the coplanar waveguide transmission line are formed on a dielectric substrate by printing or etching techniques. Page 19