CN105406185A - Miniature dual-band broadband patch antenna - Google Patents

Abstract

The invention discloses a small dual-band broadband patch antenna, which includes a ground plate, a dielectric substrate, a feed network and a radiation patch. The thickness of the dielectric substrate is 1.6mm, the ground plate is arranged on one side of the The radiation patch is arranged on the other side of the dielectric substrate, and the left and right sides of the radiation patch are symmetrically provided with rectangular grooves, the lower end of the radiation patch is connected to the feed network, and the ground plate A first rectangular groove is provided in the middle of the upper end, and a second rectangular groove and a third rectangular groove are symmetrically arranged on both sides of the first rectangular groove. The antenna of the invention achieves good impedance matching in two working frequency bands of 3.1-4.85GHz and 7.85-11.4GHz. At the same time, it can effectively suppress the interference caused by WLAN (5.15-5.35GHz) wireless communication, X-band (downlink frequency band is 3.7-4.2GHz) satellite communication, etc. The antenna of the invention is simple in structure, small in size, easy to manufacture, suitable for wireless communication systems, and has broad application prospects.

Description

A Small Dual-Band Broadband Patch Antenna

technical field

The present invention relates to the technical field of antennas, and more specifically relates to a small dual-band wideband patch antenna.

Background technique

The broadband antenna was proposed and applied only after the antenna appeared and achieved great development. Its important characteristics are broadband and large-scale coverage. It is mainly used to transmit and receive signals for multiple applications at the same time. For example, it can work simultaneously in Broadband antennas for WiMAX band and C-band. In the existing communication technology, the frequency hopping rate is constantly increasing, and the frequency hopping range is constantly increasing. The ordinary narrowband antenna can no longer adapt to this change and the requirements of communication. Moreover, if multiple antennas are arranged in a small space, the interference between the antennas will be serious, which will affect the communication quality, which also requires the antenna to have a wider working frequency band.

On the other hand, the rapid development of wireless communication has provided a broad development space for the proposal and application of various antennas. In the 1960s, Ultra-wideband (UWB) technology began to enter people's field of vision and gained develop. As a kind of broadband antenna, ultra-wideband antenna has the incomparable advantages of other narrowband antennas, such as high data rate and low loss, and has become an important research topic in the field of communication. However, with the emergence of various applications, issues such as the shortage of frequency band resources and the overlapping of working frequency bands have also attracted much attention. In 2002, the Federal Communications Commission (FCC) of the United States classified the 3.1-10.6 GHz frequency band as an ultra-wideband civil use frequency band to alleviate the shortage of frequency band resources and meet the needs of high-speed communication.

At present, the design and application of broadband and ultra-wideband antennas have become the focus of fierce competition in the field of wireless communications. In broadband communication systems, the features of antennas such as miniaturization, low cost, simplification, and ease of integration have also become important indicators for evaluating antenna practicability and cost performance.

Contents of the invention

The purpose of the present invention is to overcome the deficiencies in the prior art and provide a small broadband patch antenna with dual working frequency bands. The two working frequency bands are 3.1-4.85GHz and 7.85-11.4GHz respectively. In the frequency band, the antenna achieves good impedance matching. At the same time, the antenna can also be regarded as an ultra-wideband antenna with a frequency band of 3.1-11.4GHz and a notch characteristic for the 4.85-7.85GHz frequency band, which can effectively suppress WLAN (5.15-5.35GHz) wireless communication, X-band (downlink The frequency band is 3.7-4.2GHz) interference caused by satellite communications, etc. The antenna of the invention is simple in structure, small in size, easy to manufacture, suitable for wireless communication systems, and has broad application prospects.

The purpose of the present invention is achieved through the following technical solutions:

A small dual-band broadband patch antenna, including a ground plane, a dielectric substrate, a feed network and a radiation patch, the thickness of the dielectric substrate is 1.6mm, the ground plane is set on one side of the dielectric substrate, the feed network and the radiation patch It is arranged on the other side of the dielectric substrate, and the left and right sides of the radiation patch are symmetrically provided with rectangular grooves, the lower end of the radiation patch is connected to the feeding network, and the middle part of the upper end of the ground plate is provided with The first rectangular groove, the two sides of the first rectangular groove are symmetrically provided with a second rectangular groove and a third rectangular groove.

The length of the rectangular groove is 14mm, and the depth is 2mm.

The length of the first rectangular groove is 6mm, and the depth is 1.5mm.

Both the length of the second rectangular groove and the third rectangular groove are 6mm, and the depth is 3mm.

The dielectric substrate is made of epoxy resin.

The relative permittivity of the dielectric substrate is 4.4, and its dielectric loss tangent is 0.02.

The standard size of the dielectric substrate is 25mm×28mm.

Compared with the prior art, the beneficial effects brought by the technical solution of the present invention are:

1. The left and right sides of the radiation patch of the antenna of the present invention are symmetrically provided with rectangular grooves with a depth of 2mm, and the middle part of the upper end of the ground plate is provided with a first rectangular groove with a depth of 1.5mm. The two sides of the first rectangular groove The second rectangular groove and the third rectangular groove with a depth of 3 mm are symmetrically arranged on the side, so that the bandwidth of the antenna of the present invention is 3.1-4.85 GHz and 7.85-11.4 GHz. In this working frequency band, the antenna achieves good Impedance matching, the return loss is as low as -42dB, and it can be used as an ultra-wideband antenna with notch characteristics; it can be seen that the radiation can be greatly changed through the rectangular groove structure set on the radiation patch and the ground plate The current distribution characteristics of the patch and the ground plate increase the length of the surface current, which can not only reduce the size of the antenna, but also reduce the low frequency, improve the impedance matching degree within the effective bandwidth, and improve the performance of the antenna.

2. The antenna of the present invention is through simulation analysis, and its bandwidth is 3.1-4.85GHz and 7.85-11.4GHz, and the return loss of the antenna is less than -10dB in the effective bandwidth, and the voltage standing wave ratio VSWR<2; the antenna has two operating frequency bands The wideband antenna can be regarded as an ultra-wideband antenna with a frequency band of 3.1-11.4GHz and a notch characteristic for the 4.85-7.85GHz frequency band. The notch characteristic generated in the 4.85-7.85GHz frequency band can well suppress The interference caused by WLAN (5.15-5.35GHz) wireless communication, X-band (3.7-4.2GHz downlink frequency band) satellite communication, etc., thus improving the practicability of the antenna.

3. The size of each component and structure in the antenna of the present invention is obtained through precise design after simulation experiments. Changing any one of the sizes will affect the performance of the antenna of the present invention. The antenna has a reasonable design and a simple structure.

4. The antenna of the present invention adopts the microstrip line as the feeding network, which is a novel, miniaturized ideal antenna designed based on the typical structure of the microstrip line feeding; and has good radiation performance, which meets the needs of broadband antennas and band Requirements for the design of ultra-wideband antennas.

Description of drawings

Fig. 1 is a structural schematic diagram of the present invention.

Fig. 2 is a schematic side view of the structure of the present invention.

Fig. 3 is a schematic diagram of the structural dimensions of a specific embodiment of the present invention.

Fig. 4 is the simulation result of the return loss of four kinds of antennas with different structures.

Fig. 5 is the simulation result of the return loss of the antenna with only the ground plate having a different structure.

Fig. 6 shows the return loss simulation results of antennas with different depths of rectangular grooves only in the radiating patch.

Fig. 7(a) and Fig. 7(b) are the radiation patterns of the antenna of the present invention at two frequencies of 4GHz and 10GHz respectively.

Reference signs: 1-ground plate 2-dielectric substrate 3-feeding network 4-radiation patch 5-rectangular groove 6-first rectangular groove 7-second rectangular groove 8-third rectangular groove

detailed description

Below in conjunction with accompanying drawing, the present invention will be further described:

As shown in Figure 1 and Figure 2, a small dual-band broadband patch antenna includes a ground plate 1, a dielectric substrate 2, a feed network 3 and a radiation patch 4, and the dielectric substrate 2 is made of epoxy resin (FR4Epoxy) , the relative permittivity of the dielectric substrate 2 is 4.4, and its dielectric loss tangent is 0.02.

The antenna in this embodiment is fabricated on a dielectric substrate 2 with a size of 25mm×28mm by etching method, the thickness of the dielectric substrate 2 is 1.6mm, the ground plate 1 is printed on one side of the dielectric substrate 2, the feed network 3 and The radiation patch 4 is printed on the other side of the dielectric substrate 2, and the feed network 3 adopts a typical microstrip line feeding feeding mode. The left and right sides of the radiation patch 4 are symmetrically etched with rectangular grooves 5, The length of the rectangular groove 5 is 14mm, and the depth is 2mm; the lower end of the radiation patch 4 is connected to the feed network 3, and the middle part of the upper end of the ground plate 1 is provided with a first rectangular groove 6, and the length of the first rectangular groove 6 is 6mm, the depth is 1.5mm, the two sides of the first rectangular groove 6 are symmetrically provided with the second rectangular groove 7 and the third rectangular groove 8, the second rectangular groove 7 and the third rectangular groove 8 The length is 6mm and the depth is 3mm. The antenna of the present invention adopts a side feed mode, and the input impedance is 50 ohms.

As shown in FIG. 3 : this figure shows the specific size parameters of the antenna of the present invention after optimized design, and the units are millimeters, wherein the thickness of the dielectric substrate 2 is 1.6 mm.

In order to study the relevant characteristics of the antenna of the present invention, using full-wave three-dimensional electromagnetic simulation software, the antennas (slotted structures with and without rectangular grooves) with different structures of radiation patch 4 and ground plate 1 are simulated and compared and analyzed to obtain the antenna return loss. And the antenna of the present invention is simulated at the frequencies of 4 and 10 GHz to obtain the radiation pattern of the antenna at the frequencies, and the simulation results are analyzed. Figure 4, Figure 5 and Figure 6 are the return loss simulation results of antennas with different structures or parameters; Figure 7(a) and Figure 7(b) are the simulation results of the radiation pattern of the antenna at 4 and 10 GHz frequencies, respectively.

As can be seen from Figure 4: (1) only the ground plate 1 of the antenna has the first, second and third rectangular grooves 6, 7, 8, and when the radiation patch 4 has no rectangular groove 5, the antenna bandwidth is 3.3- 5.0GHz and 7.7-11.6GHz, the lowest to the highest frequency bands cannot fully cover the ultra-wideband range. (2) Only the radiation patch 4 of the antenna has a symmetrically arranged rectangular groove 5 structure, and when the ground plate 1 has no rectangular groove structure, the antenna has only a small working frequency band, namely 3.3-4.2GHz. (3) When neither the radiation patch 4 nor the ground plate 1 of the antenna has a rectangular groove structure, the antenna still has only a small working frequency band, namely 3.6-4.5 GHz. (4) When both the radiation patch 4 and the ground plate 1 of the antenna have the above-mentioned groove structure, which is the antenna structure proposed by the present invention, the bandwidth of the antenna is 3.1-4.85GHz and 7.85-11.4GHz, and in the working frequency band, The antenna achieves good impedance matching, the return loss is as low as -42dB, and it can be used as an ultra-wideband antenna with notch characteristics. It can be seen that when both the radiation patch 4 and the ground plate 1 of the antenna have the rectangular groove structure proposed by the antenna of the present invention, the rectangular groove structure can greatly change the current distribution characteristics on the radiation patch 4 and the ground plate 1 , increasing the length of the surface current can not only reduce the size of the antenna, but also reduce the low frequency, improve the impedance matching degree within the effective bandwidth, and improve the performance of the antenna.

In addition, it can also be seen from Fig. 4 that in the two operating frequency bands, the return loss of the antenna of the present invention is below -10dB, and even reaches -42, -38dB near the frequency points of 4 and 10.5GHz, realizing a good performance. Impedance matching.

It can be seen from Fig. 5 that when the radiation patch 4 maintains a symmetrical rectangular groove 5 structure and only the structure of the ground plane 1 changes, the performance of the antenna will still change accordingly: (1) When the ground plane 1 has only the first When a rectangular groove 6 is used, the antenna has only a relatively narrow bandwidth, namely 3.3-4.2 GHz, within the considered frequency range. (2) When the ground plate 1 only has the second rectangular groove 7 and the third rectangular groove 8, the antenna bandwidth is 3.1-5.1 GHz and 7.5-11.4 GHz, but the impedance matching degree in the high frequency band is poor. (3) When the ground plate 1 has the first, second and third rectangular grooves 6, 7, 8, the bandwidth of the antenna is 3.1-4.85GHz and 7.85-11.4GHz, and the antenna has good impedance in the working frequency band Matching, the performance is more superior.

It can be seen from FIG. 6 that even if the radiation patch 4 of the antenna has a similar rectangular groove 5 structure, the depth of the rectangular groove 5 will affect the performance of the antenna. When the ground plate 1 has the first and second and the third rectangular groove 6, 7, 8, only change the depth of the rectangular groove 5 in the radiation patch 4, it can be found that: when the depth of the rectangular groove 5 is 2mm, the ideal antenna performance is obtained; When the depth of the groove 5 is reduced to 1mm, the working frequency band of the antenna has a small shift to the right, and the impedance matching degree of the two frequency bands becomes worse; when the depth of the rectangular groove 5 is increased to 3mm, the working frequency band of the antenna has a small left shift. shift, the degree of impedance matching will also deteriorate.

From the return loss simulation results of the above antennas with different structures and parameters, it can be seen that the parameters such as the rectangular groove structure and the depth of the rectangular groove on the radiation patch 4 and the ground plate 1 can match the bandwidth and impedance of the antenna. However, the antenna of the present invention has a good antenna structure and parameter settings.

It can be seen from Fig. 7(a) and Fig. 7(b) that the radiation patterns of the antenna of the present invention on the E plane and the H plane are approximately in the shape of an inverted "8" (a small amount of side lobes appear in the high frequency part) and nearly omnidirectional radiation characteristics, and the maximum gains of the antenna at the two frequency points of 4 and 10GHz are 2.6 and 1.0dB respectively. Among them, the E plane refers to the directional diagram section parallel to the direction of the electric field; the H surface refers to the directional diagram section parallel to the magnetic field direction.

To sum up: the return loss of the antenna of the present invention in the 3.1-4.85GHz and 7.85-11.4GHz frequency bands is less than -10dB, and has good radiation performance, which meets the requirements of broadband antenna design.

Claims (7)

1. a small capacity double bandwidth paster antenna, comprise ground plate, medium substrate, feeding network and radiation patch, it is characterized in that, the thickness of medium substrate is 1.6mm, the side of medium substrate is located at by ground plate, feeding network and radiation patch are arranged on the opposite side of medium substrate, what the left and right sides of described radiation patch was symmetrical is provided with rectangular recess, the lower end of described radiation patch is connected with feeding network, the upper center of described ground plate is provided with the first rectangular recess, what the both sides of described first rectangular recess were symmetrical is provided with the second rectangular recess and the 3rd rectangular recess.

2. a kind of small capacity double bandwidth paster antenna according to claim 1, is characterized in that, the length of described rectangular recess is 14mm, and the degree of depth is 2mm.

3. a kind of small capacity double bandwidth paster antenna according to claim 1, is characterized in that, the length of described first rectangular recess is 6mm, and the degree of depth is 1.5mm.

4. a kind of small capacity double bandwidth paster antenna according to claim 1, it is characterized in that, the length of described second rectangular recess and the 3rd rectangular recess is 6mm, and the degree of depth is 3mm.

5. a kind of small capacity double bandwidth paster antenna according to claim 1, it is characterized in that, described medium substrate is made up of epoxy resin.

6. a kind of small capacity double bandwidth paster antenna according to claim 1 or 5, it is characterized in that, the relative dielectric constant of described medium substrate is 4.4, and its dielectric loss tangent value is 0.02.

7. a kind of small capacity double bandwidth paster antenna according to claim 1 or 5, it is characterized in that, the specification of described medium substrate is 25mm × 28mm.