CN108172991B - A kind of super wide band plane single pole sub antenna - Google Patents

Abstract

The invention discloses a kind of super wide band plane single pole sub antennas, comprising: medium substrate, monopole radiation patch, lumped device and earth plate.Monopole radiation patch is made of monopole antenna main body and top load.Monopole radiation patch uses triangle corner cut close to ground plate section, is mainly used for the impedance matching of high frequency section.The lamped element of antenna body load is mainly used for reducing the working frequency range of antenna and smooth antenna in the gain of entire frequency range；Monopole top loads a plurality of rectangle open circuit minor matters, increases the capacitor between antenna and floor, further decreases the working frequency range of antenna.Open circuit minor matters of the present invention by load lamped element and addition over the ground, effectively reduce antenna size while keeping excellent ultra wide band characteristic, the application convenient for antenna in monitoring field.

Description

An Ultra-Wideband Planar Monopole Antenna

technical field

The invention belongs to the technical field of antennas, in particular to an ultra-wideband (UWB) antenna.

Background technique

With the rapid development of radio technology, the demand for radio frequency resources is increasing, and radio monitoring and management are facing more challenges. As an important part of radio monitoring, the monitoring system puts forward higher and higher requirements for the wide frequency band and high gain of the front-end monitoring antenna. At the same time, with the continuous development of low-altitude electronic equipment, such as low-altitude flying drone technology, handheld monitoring equipment is facing greater market demand. Traditional monitoring antennas can no longer meet the needs of the application. Therefore, it is particularly urgent to design a monitoring antenna with wider frequency band, higher gain, smaller size and longer monitoring distance. At present, the antenna forms used in monitoring antennas mainly include monopole antennas, etc. Scholars at home and abroad have successively proposed various designs of miniaturized broadband monopole antennas. In the case of lower frequencies, the size of the antenna is still large, which is not suitable for some applications of handheld monitoring equipment.

To sum up, the existing monopole monitoring antennas still have certain limitations in terms of miniaturization, broadband, and high gain.

Contents of the invention

Purpose of the invention: Aiming at the above-mentioned prior art, an ultra-wideband planar monopole antenna is proposed to solve the deficiencies of existing monitoring antennas in terms of miniaturization, broadband, and high gain.

Technical solution: an ultra-wideband planar monopole antenna, comprising:

a dielectric substrate; a grounding plate; the dielectric substrate is fixedly connected to the grounding plate;

A monopole radiation patch, including a monopole antenna body and an antenna top loading; the monopole antenna body is composed of three sections of triangular-cut copper-clad patches; the monopole radiation patch is close to the ground The floor part adopts a triangular cut corner; a feed port is provided between the monopole radiation patch and the ground plate;

The loading on the top of the antenna includes extending open branches on both sides of the top of the monopole antenna main body, the open branches on both sides are symmetrical to each other, and the open branches are parallel to the main body of the monopole antenna;

A lumped device, including a first lumped device loaded on a copper-clad patch between the top and middle of the monopole antenna body, a second lumped device loaded on a copper-clad patch between the middle and the bottom, and the feeder The electrical port loads the third lumped device.

Further, the dielectric substrate is a Rogers RT5880 dielectric board with a dielectric constant of 2.2, with a width of 12 cm and a height of 35 cm.

Further, the monopole radiation patch is a copper-clad structure on one side of a dielectric substrate.

Further, the overall height of the monopole radiation patch is 34 cm, and the width is 12 cm.

Further, the open branch on each side includes two independent rectangular branches, each rectangular branch is 0.8 cm wide and 6 cm high, and the distance between adjacent rectangular open branches is 0.9 cm.

Further, the copper-clad patch-loaded lumped device part of the monopole antenna body adopts triangular cut corners.

Further, the feed port adopts a 50ohm coaxial feed interface.

Further, the first lumped device includes a series inductor with an inductance value of 2nH, and the loading position is 28.45cm away from the ground plate; the second lumped device includes an inductor with an inductance value of 1uH and a resistance value of 750ohm The resistors are connected in parallel, and the loading position is 19.25cm away from the ground plate; the third lumped device includes two sets of 200ohm resistors and 4nH inductors connected in series, and then connected in parallel, and the loading position is the feed port.

Further, the dielectric substrate and the grounding plate are fixed by an L-shaped stand.

Beneficial effects: the ultra-wideband planar monopole antenna provided by the present invention is loaded with lumped elements and rectangular open-circuit branches, so that the antenna can be miniaturized and has the characteristics of wide frequency band and high gain, and the overall size is 35×12cm ² ( About 0.023λ×0.008λ@200MHz). The rectangular open-circuit stub loaded on the top of the antenna increases the capacitance between the antenna and the floor, which can reduce the operating frequency of the antenna without increasing the size of the antenna. The lumped device loaded on the main body of the antenna can also reduce the operating frequency of the antenna without increasing the size of the antenna, smooth the gain of the antenna in the entire frequency band, and facilitate the integration of the subsequent circuit. By loading lumped elements and rectangular open stubs, the size of the antenna is effectively reduced.

The invention considers the influence of the antenna floor on the performance of the antenna. The monopole radiation patch close to the ground plate adopts triangular cut corners, which improves the impedance matching between the patch and the ground plate, and optimizes the performance near high frequencies. The two connection parts of the main body of the monopole antenna adopt the technology of triangular cut angle, which reduces the impedance mismatch of the loading connection part of the lumped device.

Compared with the existing monitoring antenna, the ultra-wideband planar monopole antenna provided by the present invention has the following significant advantages: (1) on the basis of the classic planar monopole antenna, lumped devices are loaded in sections, By adjusting the value of the loaded lumped device, the current path is extended and the minimum operating frequency of the antenna is reduced without increasing the size of the antenna. By adjusting the position of loading the lumped device, the gain flatness of the antenna in the whole frequency band can be improved, so that the antenna has a smooth gain curve in the whole frequency band, which provides good performance for the follow-up monitoring system.

(2) Loading a rectangular open-circuit branch on the top of the antenna increases the capacitance between the monopole antenna and the floor without increasing the longitudinal size of the antenna, further reduces the minimum operating frequency of the antenna, and makes the size of the antenna smaller. The overall size is 35×12cm ² .

(3) By combining lumped element loading and top open-circuit branch loading technology, the invention greatly reduces the size of the antenna compared with the classic planar monopole, and the antenna has a simple structure, high reliability, small size, and is easy to form an array.

Description of drawings

FIG. 1 is a structural diagram of an ultra-wideband planar monopole antenna provided by an embodiment of the present invention.

Fig. 2 is a schematic structural diagram of a lumped device, wherein (a) is a schematic structural diagram of a first lumped device, (b) is a schematic structural diagram of a second lumped device, and figure (c) is a schematic structural diagram of a third lumped device.

Fig. 3 is a simulation diagram of voltage standing wave ratio of the ultra-wideband planar monopole antenna provided by the embodiment of the present invention.

Fig. 4 is a simulation diagram of the maximum gain curve of the ultra-wideband planar monopole antenna provided by the embodiment of the present invention.

Fig. 5 is a radiation pattern of the ultra-wideband planar monopole antenna provided by an embodiment of the present invention at different frequencies.

Detailed ways

The present invention will be further explained below in conjunction with the accompanying drawings.

As shown in Figure 1, an ultra-wideband planar monopole antenna includes: a dielectric substrate 5, a monopole radiation patch and a lumped device arranged on the surface of the dielectric substrate 5, and a ground plate arranged at one end of the dielectric substrate 5 7.

The dielectric substrate 5 is a Rogers RT5880 dielectric board with a dielectric constant of 2.2, with a width of 12 cm and a height of 35 cm. The dielectric substrate 5 and the ground plate 7 are fixed by an L-shaped stand piece 8 . The monopole radiating patch is a copper-clad structure on one side of the dielectric substrate, with an overall height of 34 cm and a width of 12 cm, including the monopole antenna main body 6 and the antenna top loading. Wherein, the main body 6 of the monopole antenna is composed of three sections of copper-clad patches with triangular cut corners. The loading on the top of the antenna includes open circuit branches 4 extending on both sides of the top of the monopole antenna main body 6, the open circuit branches on both sides are symmetrical to each other, and the open circuit branches are parallel to the monopole antenna main body 6; the open circuit branches 4 on each side include two Independent rectangular branches, each rectangular branch is 0.8cm wide, 6cm high, and the interval between adjacent rectangular branches is 0.9cm. A feed port is provided between the monopole radiation patch and the ground plate, and the feed port adopts a 50ohm coaxial feed interface.

The lumped device includes the first lumped device 1 loaded on the copper-clad patch between the top and the middle of the monopole antenna body, the second lumped device 2 loaded on the copper-clad patch between the middle and the bottom, and the feeding The port loads the third lumped device 3 . Among them, the first lumped device 1 includes a series inductor with an inductance value of 2nH, and the loading position is 28.45cm away from the ground plate; the second lumped device 2 includes an inductor with an inductance value of 1uH and a resistor with a resistance value of 750ohm connected in parallel, The loading position is 19.25cm away from the grounding plate; the third lumper includes two sets of 200ohm resistors and 4nH inductors connected in series, then connected in parallel, and loaded on the feed port. The part of the copper-clad patch loaded lumped device of the monopole antenna main body 6 adopts triangular cut corners.

The application effect of the present invention will be described in detail below in conjunction with simulation.

Figure 3 shows the simulated VSWR of the present invention. It can be seen that in the entire frequency band of 20MHZ-6GHZ, the typical value of the voltage standing wave ratio of the antenna is basically less than 2, and the impedance matching is good.

Fig. 4 shows the maximum gain of the simulation of the present invention. It can be seen that as the operating frequency of the antenna increases, the antenna gain increases slowly from -41dB to 7dB, and the gain change trend is gentle in the entire frequency band, which is conducive to the integration of the post-amplifier. The smoothly changing gain is mainly realized by adjusting the value of the lumped element and the position of the element in parts 1 and 2 in Fig. 1 .

Fig. 5 has provided the radiation direction schematic diagram of the present invention, and wherein figure (a) is 30MHz, the direction diagram of xoy plane, figure (b) is 30MHZ, the direction diagram of yoz plane, figure (c) is 500MHZ, the direction of xoy plane Figure, Figure (d) is 500MHZ, yoz plane direction diagram. It can be seen that in the yoz plane, the antenna basically maintains a good omnidirectional radiation characteristic.

In summary, the ultra-wideband planar monopole antenna of the present invention greatly reduces the minimum operating frequency of the antenna without increasing the size of the antenna by loading a passive lumped device and an open-circuit stub on the top of the antenna, so that the antenna's The structure is more compact. The antenna of this design scheme has a simple structure, is easy to process, has a flat gain in a wide frequency band, is easy to form an array, and has a good application prospect.

The above is only a preferred embodiment of the present invention, it should be pointed out that, for those of ordinary skill in the art, without departing from the principle of the present invention, some improvements and modifications can also be made, and these improvements and modifications can also be made. It should be regarded as the protection scope of the present invention.

Claims (8)

1. An ultra-broadband planar monopole antenna, characterized in that, comprising: a dielectric substrate; a grounding plate; the dielectric substrate is fixedly connected to the grounding plate; A monopole radiation patch, including a monopole antenna body and an antenna top loading; the monopole antenna body is composed of three sections of triangular-cut copper-clad patches; the monopole radiation patch is close to the ground The floor part adopts a triangular cut corner; a feed port is provided between the monopole radiation patch and the ground plate; The loading on the top of the antenna includes extending open branches on both sides of the top of the monopole antenna main body, the open branches on both sides are symmetrical to each other, and the open branches are parallel to the main body of the monopole antenna; A lumped device, including a first lumped device loaded on a copper-clad patch between the top and middle of the monopole antenna body, a second lumped device loaded on a copper-clad patch between the middle and the bottom, and the feeder The electrical port loads the third lumped device; The first lumped device includes a series inductor with an inductance value of 2nH, and the loading position is 28.45 cm from the ground plane; the second lumped device includes an inductor with an inductance value of 1 uH and a resistor with a resistance value of 750 ohm parallel connection, the loading position is 19.25 cm away from the ground plate; the third lumped device includes two sets of 200 ohm resistors and 4 nH inductance in series, and then parallel connection, the loading position is the feed port. 2. The ultra-broadband planar monopole antenna according to claim 1, wherein the dielectric substrate adopts a Rogers RT5880 dielectric plate with a dielectric constant of 2.2, a width of 12 cm, and a height of 35 cm. 3. The ultra-wideband planar monopole antenna according to claim 1, wherein the monopole radiating patch is a copper-clad structure on one side of a dielectric substrate. 4. The ultra-wideband planar monopole antenna according to claim 1, wherein the overall height of the monopole radiation patch is 34 cm, and the width is 12 cm. 5. The ultra-broadband planar monopole antenna as claimed in claim 1, wherein the open circuit branches on each side include 2 independent rectangular branches, each rectangular branch is 0.8 cm wide and 6 cm high, and adjacent rectangular open circuits The distance between branches is 0.9 cm. 6 . The ultra-wideband planar monopole antenna according to claim 1 , wherein the copper-clad patch-loaded lumped device part of the monopole antenna body adopts a triangular corner cutting technology. 7 . 7. The ultra-wideband planar monopole antenna according to claim 1, wherein the feed port adopts a 50 ohm coaxial feed interface. 8. The ultra-wideband planar monopole antenna according to claim 1, wherein the dielectric substrate and the ground plate are fixed by an L-shaped stand.