TWI467852B - A planar inverted l-shaped monopole antenna with multi-band operation for wimax system - Google Patents

Description

Planar inverted L-type multi-frequency monopole antenna for WiMAX system

The invention relates to the design of two L-shaped metal sheets for the antenna radiation structure. The front side is inverted with an L-shaped metal sheet, and the width of the metal sheet is increased at the middle arm of the path to effectively adjust the impedance matching, and the path can control the low frequency and high frequency modes. It has a wide-band operating characteristic, while the back L-type parasitic metal plate can excite the mid-band mode to meet the bandwidth requirements of WiMAX systems, and has a good isotropic radiation field and smoothness in its operating frequency range. Peak gain characteristics.

In any wireless communication system, the antenna occupies a very important position, and in the near ten The fastest antenna development in the world should belong to the planar antenna, which has a low profile, a small size, a light weight, a low cost, and is easy to manufacture. Highly reliable features can be attached to the surface of any object, making planar antennas widely used. However, many antennas have been proposed for antennas used in WiMAX systems, but most of them are limited to single-frequency operation and their volume is relatively large. Large, the research and development results of miniaturized multi-frequency or wide-band planar antennas are paid for. In the trend of smaller and smaller mobile devices, the requirements of personal communication products are becoming more and more demanding, and the design is light, thin, and inexpensive. The basic requirement is to design a suitable antenna in a limited space. The form and size of the antenna itself become the first requirement. In addition, the antenna bandwidth, gain, efficiency, and radiation of the antenna. Radiation Patterns, etc., are all in-depth research directions.

We propose a planar inverted L-type multi-frequency monopole antenna for WiMAX systems. This antenna can stimulate the operating modes of three WiMAX systems of 2.6/3.5/5.5 GHz by coplanar waveguide feeding, with a bandwidth of 260/. At 1050/2130MHz, the antenna peak gain and radiation efficiency are 2.8/3.2/4.4dBi and 68/70/95%, respectively, and the XY-plane has an approximately isotropic radiation pattern.

1 is an embodiment of an antenna of the present invention, comprising: a dielectric substrate 10, the dielectric substrate is provided with two metal surfaces, the metal surface comprises: a first ground metal surface 111, a second ground metal surface 112, a The signal is fed into the microstrip metal piece 12, a signal feeding position 13, and an inverted L-shaped metal piece 14, the inverted L-shaped metal surface comprising: a first arm 141 of an inverted L-shaped radiating metal piece, and an inverted L-shaped radiation The middle arm 142 of the metal piece, the second arm 143 of the inverted L-shaped radiating metal piece, and a back L-shaped radiating metal piece 15 comprising: a first arm 151 of a back L-shaped radiating metal piece a second arm 152 of the back L-shaped radiation metal sheet.

The first arm 141 of the inverted L-shaped radiating metal piece 14 is connected to the intermediate arm 142 of the inverted L-shaped radiating metal piece 14, and the second arm 143 of the inverted L-shaped radiating metal piece is The intermediate arms 142 of the inverted L-shaped radiating metal sheets are connected in a vertical manner, and the first arm 151 of the back L-shaped radiating metal sheet and the second arm 152 of the back L-shaped radiating metal sheet are connected in a perpendicular manner.

Figure 2 is a graph showing the return loss experimental measurement results of an embodiment of the antenna of the present invention, wherein the vertical axis represents the return loss (dB) and the horizontal axis represents the operating frequency (GHz); as shown in Fig. 2, the obtained test result The return loss value is greater than or equal to 10 dB as the standard, and the bandwidth is 260/1050/2130 MHz, which can meet the bandwidth requirement of the WiMAX 2.6/3.5/5.5 GHz system, indicating that the embodiment of the antenna of the present invention has good in each frequency band. Operating characteristics.

Fig. 3, Fig. 4 and Fig. 5 are measurement results of radiation field type measurements of 2.6 GHz, 3.5 GHz and 5.5 GHz, respectively, of an embodiment of the antenna of the present invention. Among them, the X-Y plane is a good isotropic radiation field type, and the X-Z plane and the Y-Z plane are obtained by a broad-side radiation field type (Broadside Radiation), which is a typical monopole antenna radiation field type.

6 , 7 and 8 are experimental results of antenna peak gains of the antennas of the present invention in the low frequency, intermediate frequency and high frequency bands respectively, the vertical axis represents the gain value (dBi), and the horizontal axis represents the operation. Frequency (GHz), from the experimental results, the antenna gain of the antenna is 2.8/3.2/4.4 dBi in three operating frequency bands, respectively, and has good operational characteristics, that is, the embodiment of the antenna of the present invention can produce good Send and receive effects.

In summary, the planar inverted L-type multi-frequency monopole antenna of the WiMAX system of the present invention has the characteristics of three-frequency operation and approximate isotropic radiation field type; moreover, it is not only simple to manufacture, low in cost, small in size, and proves the present invention. The industrial application value of the antenna is extremely high enough to meet the scope of the invention.

The embodiments described in the above description are merely illustrative of the principles of the invention and its advantages, and are not intended to limit the invention. The scope of the invention should be as set forth in the appended claims.

10‧‧‧Media substrate

111‧‧‧First grounded metal surface

112‧‧‧Second grounded metal surface

12‧‧‧Signal feeding microstrip metal wire

13‧‧‧ Signal feed location

14‧‧‧Inverted L-shaped radiation metal sheet

15‧‧‧L-type radiation metal sheet on the back

141‧‧‧ First arm of inverted L-shaped radiation metal sheet

142‧‧‧Intermediate arm of inverted L-shaped radiation metal sheet

143‧‧‧ Second arm of inverted L-shaped radiation metal sheet

151‧‧‧The first arm of the L-shaped radiation metal sheet on the back

152‧‧‧The second arm of the L-shaped radiation metal sheet on the back

1 is a structural view showing an embodiment of a planar inverted L-type multi-frequency monopole antenna of the present invention.

Figure 2 is a graph showing the measured return loss measurement results for an embodiment of the antenna of the present invention.

Figure 3 is a graph showing the measurement results of the radiation field type in the X-Y plane operating at 2.6 GHz, 3.5 GHz, and 5.5 GHz according to an embodiment of the antenna of the present invention.

Figure 4 is an embodiment of an antenna of the present invention operating at 2.6 GHz, 3.5 GHz, and 5.5 GHz. Radiation field measurement results of the X-Z plane.

Fig. 5 is a measurement result of radiation field type in the Y-Z plane operating at 2.6 GHz, 3.5 GHz and 5.5 GHz according to an embodiment of the antenna of the present invention. .

Figure 6 is a graph showing the measurement results of the antenna peak gain of the antenna in the low frequency band according to an embodiment of the antenna of the present invention.

Figure 7 is a graph showing the measurement results of the antenna peak gain of the mid-band in an embodiment of the antenna of the present invention.

Figure 8 is a graph showing the measurement results of the antenna peak gain of the antenna in the high frequency band according to an embodiment of the antenna of the present invention.

10‧‧‧Media substrate

111‧‧‧First grounded metal surface

112‧‧‧Second grounded metal surface

12‧‧‧Signal feeding microstrip metal wire

13‧‧‧ Signal feed location

14‧‧‧Inverted L-shaped radiation metal sheet

15‧‧‧L-type radiation metal sheet on the back

141‧‧‧ First arm of inverted L-shaped radiation metal sheet

142‧‧‧Intermediate arm of inverted L-shaped radiation metal sheet

143‧‧‧ Second arm of inverted L-shaped radiation metal sheet

151‧‧‧The first arm of the L-shaped radiation metal sheet on the back

152‧‧‧The second arm of the L-shaped radiation metal sheet on the back

Claims (4)

A planar inverted L-type multi-frequency monopole antenna comprising: a dielectric substrate having a first grounded metal surface, a second grounded metal surface, an inverted L-shaped radiating metal piece, and a back L-shaped radiating metal piece; a microstrip metal wire; a microstrip metal wire comprising: a rectangular metal wire connected to a first arm of an inverted L-shaped radiating metal piece for feeding electromagnetic wave signals; and an inverted L-shaped radiating metal piece having a a first arm, an intermediate arm and a second arm; and a back L-shaped radiating metal piece having a first arm and a second arm; electrically connected to a microstrip metal wire for transmitting and receiving electromagnetic wave signals; Wherein the first arm of the inverted L-shaped radiating metal piece is connected to the intermediate arm of the inverted L-shaped radiating metal piece, and the second arm of the inverted L-shaped radiating metal piece and the intermediate arm of the inverted L-shaped radiating metal piece The first arm of the back L-shaped radiating metal piece is connected to the second arm of the back L-shaped radiating metal piece in a perpendicular manner. The planar inverted-L-type multi-frequency monopole antenna for a WiMAX system according to claim 1, wherein the feed point is located substantially below the antenna and is located at a position of the microstrip metal line and the grounded metal surface as a signal feed. . The flat inverted L-type multi-frequency monopole antenna for the WiMAX system according to claim 1, wherein the starting arm of the inverted L-shaped metal piece is connected to one end of the microstrip wire and connected to the positive end of the signal. The planar inverted-L-type multi-frequency monopole antenna for a WiMAX system according to claim 1, wherein the starting arm of the back L-type radiating metal piece and the starting arm of the inverted L-shaped radiating metal piece are formed by a dielectric substrate Parasitic coupling is performed to transmit electromagnetic wave signals.