CN103094676B - With T-type structure and the ultra-wideband antenna with band-stop response mating minor matters - Google Patents

Abstract

The invention discloses an ultra-wideband antenna with a T-shaped structure and a matching branch with band-rejection characteristics. It is composed of a T-shaped structural strip, a circular radiator, a rectangular matching branch, a transition matching branch, a coplanar metal plate, a microstrip feeder and a dielectric substrate. Among them, a radiator with a circular structure is added to the front end of the microstrip feeder to change the path of the surface current of the antenna and make the antenna work in the ultra-wideband frequency band. Three matching branches are designed at the front end of the circular radiator to increase the resonant frequency point of the antenna and achieve the purpose of increasing the bandwidth of the antenna. A T-shaped structural strip is embedded inside the circular radiator to realize the band-stop function of the antenna, so that the antenna has a stop band in the ultra-wideband frequency band. The antenna designed by the invention can meet the technical requirements of ultra-wideband, and realize good band-rejection characteristics between 5.1GHz and 5.8GHz. The antenna of the invention has a small and compact structure, is convenient to process, and is easy to be integrated with an active circuit, so it has a good application prospect in the ultra-wideband field.

Description

Ultra-Wideband Antenna with Band-stop Characteristic with T-shaped Structure and Matching Stubs

technical field

The invention relates to an ultra-wideband antenna with band-rejection characteristics in the field of communication, more particularly, it is realized by matching stubs with a T-shaped ring and a rectangular structure in the 3.0-11.0GHz ultra-wideband frequency band An ultra-wideband antenna for communication and with band-stop characteristics in the 5.1-5.8GHz frequency band.

Background technique

In February 2002, the Federal Communications Commission (FCC) of the United States approved the frequency band of 3.1-10.6 GHz as an available frequency band for the ultra-wideband (UWB) system. Since then, the design of wireless UWB systems has received increasing attention. UWB system has the advantages of excellent anti-multipath interference, wide frequency band and high data rate. The most important component in a wireless UWB system is the UWB antenna. The requirements for UWB antennas mainly include good impedance matching, stable gain and good omnidirectional radiation characteristics in ultra-wideband (3.0-11.0 GHz), and require miniaturized antennas and low manufacturing costs.

UWB antennas work in such a wide bandwidth, and may receive interference signals from other communication or radio frequency systems that work in this frequency band in the same environment, such as IEEE802.11a of wireless local area network (WLAN), and the frequency band works at 5.150～5.350GHz and 5.725-5.825GHz, HIPERLAN/2 frequency bands work at 5.150-5.350GHz and 5.470-5.725GHz, all of which will interfere with the ultra-wideband working system. Therefore, it is very necessary and practical to design an ultra-wideband antenna with a band-rejection function to filter out the interference of other narrow-band signals. The more common method is to add a filter behind the antenna or design multiple antennas working in different frequency bands to form stop bands with each other to filter out interference frequency band signals, but this increases the size and cost of the antenna. A more effective method is to add a T-shaped, π-shaped or U-shaped structural band to the radiating element of the antenna to change the surface current distribution of the radiating element to achieve the band-stop function, but this usually only provides a stop band and cannot completely Filter out potential distractions. The T-shaped structure can play a band-stop characteristic in the antenna. In the literature "Z.Liu, H.Deng, and X.He, A New Band-Notched UWBPrinted Monopole Antenna" (Global Symposium on Millimeter Waves, pp.291-294, 2008) and "C.Hong, C.Ling, I.Tarn, and S.Chung, Design of a Planar Ultrawideband Antenna With a New-Notch Structure" (IEEETransation on Antennas Propagation, vol.55, no.12, pp.3391 -3397, Dec.2007) carried out specific analysis. .

In addition, the UWB monopole antenna is fed by a coplanar waveguide, and is widely used in the UWB field due to its small size, impedance matching characteristics and omnidirectional radiation characteristics in UWB. Document "K.Lau, P.Li, and K.Man, A Monopolar Patch Antenna with Very Wide Impedance Bandwidth" (IEEE Transation on Antennas Propagation, vol.53, no.3, pp.1004-1010, Mar.2005) published An ultra-wideband monopole patch antenna. UWB antennas fed by coplanar waveguides have the characteristics of low profile, wide bandwidth, low power consumption, and easy integration with circuits, so they are widely used in communication systems.

Contents of the invention

The purpose of the present invention is to propose a new type of ultra-wideband antenna with T-shaped structure and matching stubs with band-rejection characteristics, which not only meets the ultra-wideband requirements proposed by the FCC, but also realizes the band-rejection function at 5.1GHz to 5.8GHz , to avoid interference between devices using antennas. The antenna has a simple structure, is easy to process, and is easy to integrate with active circuits.

A kind of ultra-broadband antenna with band-rejection characteristic with T-shaped structure and matching stub of the present invention, this ultra-broadband antenna comprises T-shaped structure band (1), circular radiator (2), the first rectangular matching stub ( 31), second rectangular matching stub (32), third rectangular matching stub (33), transition matching stub (4), microstrip feeder (5), left coplanar metal plate (61), right coplanar metal plate ( 62) and dielectric substrate (7);

The T-shaped structural belt (1) is located in the circular radiator (2);

The first rectangular matching stub (31) is located on the left side outside the circular radiator (2);

The second rectangular matching branch (32) is located above the outside of the circular radiator (2);

The third rectangular matching branch (33) is located on the left side outside the circular radiator (2);

The microstrip feeder (5) is connected below the outside of the ring radiator (2);

The left coplanar metal plate (61) is located on the left side of the microstrip feeder (5);

The right coplanar metal plate (62) is located on the right side of the microstrip feeder (5);

T-shaped structural belt (1), circular radiator (2), first rectangular matching branch (31), second rectangular matching branch (32), third rectangular matching branch (33), transitional matching branch (4), The microstrip feeder (5), the left coplanar metal plate (61) and the right coplanar metal plate (62) are etched on the dielectric substrate (7) for copper covering.

Compared with the prior art, the present invention has the following obvious outstanding substantive features and significant advantages:

1. The present invention provides a miniaturized ultra-wideband antenna that can be mass-produced and has a band-stop characteristic in the WLAN frequency band, and can effectively suppress the interference of potential WLAN frequency band signals.

2. In the present invention, the T-shaped structure belt, circular radiator, rectangular matching branch, transition matching branch, coplanar metal plate and microstrip feeder are all on the same side of the dielectric substrate, which has the advantages of compact and simple structure and convenient processing. At the same time, the entire antenna is small in size (26mm×34mm×1.6mm), light in weight, and adopts a planar structure, which is easy to integrate with active circuits.

3. The present invention adopts the structure of the T-shaped structural band embedded in the circular radiator to realize the band-stop mode. By controlling the length of the T-shaped structural band and the radius of the circular radiator, the center frequency of the stop band can be conveniently controlled, and it can be applied to various specific needs.

4. The present invention adopts three rectangular matching branches to be distributed on the circular radiator, the left and right ends, and increases the resonant frequency point of the antenna, thereby improving the standing wave ratio of the antenna at the high frequency point, widening the bandwidth of the antenna, and making the antenna Work better in the UWB band.

Description of drawings

Fig. 1 is an external structure diagram of the ultra-wideband antenna of the present invention.

FIG. 1A is a top view of the ultra-wideband antenna of the present invention.

Fig. 2 is a graph of the simulation results of the antenna standing wave ratio changing with L ₁₁ +L ₁₂ in the present invention.

Fig. 3 is a simulation result diagram of the antenna standing wave ratio with the variation of R _in the present invention.

Fig. 4 is a simulation result diagram of the antenna standing wave ratio varying with L ₃₁ in the present invention.

Fig. 5 is a graph showing the simulation results of the standing wave ratio of the antenna of the present invention.

Fig. 6 is a graph of gain simulation results of the antenna of the present invention.

Fig. 7A is a far-field radiation pattern of the antenna of the present invention at 5 GHz on the E-plane.

FIG. 7B is a far-field radiation pattern of the antenna of the present invention at 5 GHz on the H plane.

Fig. 8A is a far-field radiation pattern of the antenna of the present invention at 5.4 GHz on the E-plane.

FIG. 8B is a far-field radiation pattern of the antenna of the present invention at 5.4 GHz on the H-plane.

FIG. 9A is a far-field radiation pattern of the antenna of the present invention at 6 GHz on the E-plane.

FIG. 9B is a far-field radiation pattern of the antenna of the present invention at 6 GHz on the H plane.

Fig. 10A is a far-field radiation pattern of the antenna of the present invention at 7 GHz on the E-plane.

FIG. 10B is a far-field radiation pattern of the antenna of the present invention at 7 GHz on the H plane.

Detailed ways

The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments.

Referring to Fig. 1 and shown in Fig. 1A, the present invention is a kind of ultra-wideband antenna with band-rejection characteristic with T-shaped structure and matching branch, and this ultra-wide-band antenna comprises T-shaped structure band 1, circular radiator 2, the second A rectangular matching stub 31, a second rectangular matching stub 32, a third rectangular matching stub 33, a transitional matching stub 4, a microstrip feeder 5, a left coplanar metal plate 61, a right coplanar metal plate 62, and a dielectric substrate 7;

The T-shaped structural belt 1 is located in the circular radiator 2;

The first rectangular matching branch 31 is located on the left side outside the circular radiator 2;

The second rectangular matching branch 32 is located above the outside of the circular radiator 2;

The third rectangular matching branch 33 is located on the left side outside the circular radiator 2;

The microstrip feeder 5 is connected under the outside of the ring radiator 2;

The left coplanar metal plate 61 is located on the left side of the microstrip feeder 5;

The right coplanar metal plate 62 is located on the right side of the microstrip feeder 5;

T-shaped structure belt 1, circular radiator 2, first rectangular matching branch 31, second rectangular matching branch 32, third rectangular matching branch 33, transition matching branch 4, microstrip feeder 5, left coplanar metal plate 61 and The right coplanar metal plate 62 is etched on the dielectric substrate 7 by copper clad technology. That is to say, the T-shaped structural strip 1, the circular radiator 2, the first rectangular matching branch 31, the second rectangular matching branch 32, the third rectangular matching branch 33, the transition matching branch 4, the microstrip feeder 5, and the left coplanar The metal plate 61 and the right coplanar metal plate 62 are made of copper metal. In order to realize the integration with the active circuit, the structure designed in the present invention is small and compact, low in cost and easy to process.

In the present invention, the T-shaped structure strip 1 is embedded in the circular radiator 2, the purpose of which is to provide a 5.1GHz-5.8GHz band-rejection within the passband of the antenna. The transverse length of the T-shaped structural belt 1 is denoted as L ₁₁ and the longitudinal length is denoted as L ₁₂ , the longitudinal width of the T-shaped structural belt 1 is denoted as W ₁₁ and the lateral width is denoted as W ₁₂ , and the thickness of the T-shaped structural belt 1 is denoted as h ₁ (also the thickness of the copper pour).

In the present invention, the annular radiator 2 is connected to the front end of the microstrip feeder 5, and the annular structure changes the path of the antenna surface current, so that the energy of the antenna can be radiated outward more effectively, providing the antenna with a 3.0GHz ~11.0GHz ultra-wideband bandwidth. The inner radius of the ring radiator 2 is denoted as _Rin , the _outer radius is denoted as Router, and the height is denoted as h ₂ .

In the present invention, the purpose of respectively designing three rectangular matching stubs (the first rectangular matching stub, the second rectangular matching stub and the third rectangular matching stub) is to increase the resonant frequency point of the antenna, thereby improving the standing wave ratio characteristics of the antenna , to achieve the purpose of increasing the antenna bandwidth. The length of the first rectangular matching branch 31 is recorded as L ₃₁ , the width is recorded as W ₃₁ , and the height is recorded as h ₃₁ ; the length of the second rectangular matching branch 32 is recorded as L ₃₂ , the width is recorded as W ₃₂ , and the height is recorded as h ₃₂ ; The length of the third rectangle matching branch 33 is denoted as L ₃₃ , the width is denoted as W ₃₃ , and the height is denoted as h ₃₃ , and L ₃₃ =L ₃₁ , W ₃₃ =W ₃₁ , h ₃₁ =h ₃₂ =h ₃₃ ; the first rectangle The heights of the matching branch 31 and the third rectangular matching branch 33 from the narrow side of the dielectric substrate 7 are respectively denoted as H ₃₁ and H ₃₃ , and H ₃₁ =H ₃₃ .

In the present invention, the transition matching stub 4 is connected between the ring radiator 2 and the microstrip feeder 5 to realize the impedance matching of the antenna and effectively widen the bandwidth of the antenna. The length of transition matching stub 4 is denoted as L ₄ , the width is denoted as W ₄ , and the height is denoted as h ₄ .

In the present invention, the right coplanar metal plate 61 and the left coplanar metal plate 62 are distributed on both sides of the microstrip feeder 5, and the microstrip feeder 5 and the coplanar metal plate 6 constitute the feeding of the coplanar waveguide for the antenna. In this feeding mode, the integration of the antenna and the active circuit is facilitated. The length of the microstrip feeder 5 is marked as L ₅ , the width is marked as W ₅ , and the height is marked as h ₅ ; the length of the coplanar metal plate 6 is marked as L ₆ , the width is marked as W ₆ , and the height is marked as h ₆ .

In the present invention, on the same side of the dielectric substrate 7 are distributed a T-shaped structural strip 1, a circular radiator 2, a rectangular matching branch 3, a transition matching branch 4, a microstrip feeder 5 and a coplanar metal plate 6, The structure is small and compact. In the present invention, the dielectric substrate 7 is made of FR4 material with a dielectric constant of 4.4 and a loss tangent angle of 0.02. The length of the dielectric substrate 7 is denoted as L ₇ , the width as W ₇ , and the height as h ₇ .

In the present invention, the T-shaped structure strip 1, the ring radiator 2, the rectangular matching branch 3, the transition matching branch 4, the microstrip feeder 5 and the coplanar metal plate 6 are all made of copper or copper foil.

In the present invention, the dimensions of the T-shaped structure strip 1, the ring radiator 2, the rectangular matching branch 3, the rectangular transition branch 4, the microstrip feeder 5, and the coplanar metal plate 6 are the same in height, that is, h ₁ = h ₂ =h ₃₁ =h ₃₂ =h ₃₃ =h ₄ =h ₅ =h ₆ .

Example 1

In order to select the parameter values in Figure 1 and Figure 1A of the ultra-wideband antenna structure with band-stop characteristics, the antenna of the present invention is designed, simulated and analyzed on a computer equipped with Ansoft HFSS. The computer is a modern intelligent electronic device that can automatically and high-speed perform a large number of numerical calculations and various information processing according to pre-stored programs. The minimum configuration is CPU 2GHz, memory 2GB, hard disk 180GB; operating system is windows 2000/2003/XP. HFSS software is developed by Ansoft Company in the United States. It is a three-dimensional electromagnetic field simulation software. It applies the tangential vector finite element method to solve the electromagnetic field distribution of any three-dimensional radio frequency and microwave devices, calculate the loss caused by materials and radiation, and directly obtain the characteristics. Impedance, propagation coefficient, S-parameter and results of electromagnetic field, radiation field, antenna pattern, specific absorption rate, etc., are widely used in the design of antennas, feeders, filters, etc. calculate.

In the antenna of the present invention, the main parameters that determine the performance of the antenna are the lengths L ₁₁ and L ₁₂ of the T-shaped structure strip 1, and the length L ₃₁ of the first rectangular matching branch 31 _within the inner radius R of the circular radiator 2, so the main The performance index of the antenna designed in the present invention is achieved by adjusting the parameter values L ₁₁ +L ₁₂ , R ₂ and L ₃₁ .

In the present invention, the reason for choosing the length L ₁₁ +L ₁₂ of the T-shaped structure band 1 as the analysis parameter is: the ring radiator 2 and the T-shaped structure band 1 are equivalent to inductance and capacitance in the circuit, and in the ring radiator 2 is embedded with a T-shaped structure band 1, which causes the antenna impedance to change at the resonant frequency, resulting in an impedance mismatch and a stop band; adjust the parameters of the T-shaped structure band 1, and its resonance frequency point will also change accordingly, so that the stop band The center frequency of the T-shaped structure will also change. Since the lengths L ₁₁ and L ₁₂ of the T-shaped structure 1 are easier to adjust than the widths W ₁₁ and W ₁₂ , the lengths L ₁₁ and L ₁₁ of the T-shaped structure 1 are selected as the resonance frequency points. control parameters; and the lengths L ₁₁ and L ₁₂ of the T-shaped structure belt 1 need to be measured, and the effects produced when the lengths L ₁₁ and L ₁₂ change are equivalent, so for the convenience of analysis, L ₁₁ and L ₁₂ are combined in Take L ₁₁ +L ₁₂ together as analytical parameters.

In the present invention, the reason why the inner radius R _of the circular radiator 2 is selected as the analysis parameter is: adjusting the parameters of the circular radiator 2 will change the equivalent inductance value in the circuit, thereby changing the impedance mismatch of the antenna. degree, and then change the bandwidth of the stopband; in order to meet the purpose of antenna miniaturization, keep the _outer radius R of the circular radiator 2 unchanged, and select the _inner radius R as the control parameter of the bandwidth of the stopband, so take the _inside of R as Analysis parameters.

In the present invention, the reason for selecting the length L ₃₁ of the first rectangular matching stub 31 as the analysis parameter is: adjusting the parameters of the rectangular matching stub will change the size of the resonant frequency point at the high frequency, thereby changing the bandwidth of the passband; the rectangular matching Among the parameters of the branches, the first rectangular matching branch 31 and the third rectangular matching branch 33 are easier to adjust than the second rectangular matching branch 32, the lengths L ₃₁ and L ₃₃ are easier to adjust than the widths W ₃₁ and W ₃₃ , and the first rectangular matching branch 31 The length of is the same as the length of the third rectangular matching branch 33, that is, L ₃₁ =L ₃₃ , so L ₃₁ is taken as an analysis parameter.

Analysis of the influence of the main parameters of the antenna of the present invention on the performance of the antenna:

(A) Adjust the length of L ₁₁ + L ₁₂ in the T-shaped structure belt 1 from 7.9mm to 9.9mm, and keep other parameters as shown in Table 1. The antenna standing wave ratio is collected by HFSS simulation software (HFSS 11) The simulation result of figure (as shown in Figure 2);

(B) Adjust the inner radius R _of the circular radiator 2 from 5.2mm to 7.2mm, keep the other parameters as shown in Table 1, and use the HFSS simulation software (HFSS 11) to collect the simulation of the antenna standing wave ratio diagram Result (as shown in Figure 3);

(C) Adjust the length L ₃₁ of the first rectangular matching stub 3 from 1.9mm to 3.5mm, keep other parameters as shown in Table 1, and use the HFSS simulation software (HFSS 11) to collect the simulation of the antenna standing wave ratio diagram The result (shown in Figure 4).

It can be seen from Figure 2 that the length value of L ₁₁ +L ₁₂ has a great influence on the center frequency of the stop band. When the length value of L ₁₁ +L ₁₂ increases from 7.9mm to 9.9mm, the center frequency of the stop band changes from 5.6GHz to 4.3GHz with little effect on the passband. Therefore, the center frequency of the stop band can be adjusted by adjusting the length of L ₁₁ +L ₁₂ in the T-shaped structure band 1 .

It can be seen from Figure 3 that the length value in R _has a great influence on the stopband bandwidth. When R increases from 5.2mm _to 7.2mm, the standing wave ratio of the antenna corresponding to the center frequency of the stopband increases from 4.3 to 8.0, while the stopband The center frequency is reduced very little. Therefore, the bandwidth of the stop band can be adjusted by adjusting the length of the _inner radius R of the annular radiator 2 .

Figure 4 shows that the length of L ₃₁ has a great influence on the upper cutoff frequency of the passband. When L ₃₁ increases from 1.9mm to 3.5mm, the upper cutoff frequency of the passband decreases to 10.5GHz, while the lower cutoff frequency of the passband The cutoff frequency is basically unchanged. Therefore, the bandwidth of the passband can be adjusted by adjusting the length of L ₃₁ in the first rectangular matching stub 31 .

Using HFSS software to simulate and analyze the parameter values in the UWB antenna structure diagram with band-stop characteristics, the obtained parameters are shown in Table 1.

Table 1 The values corresponding to the parameters in the ultra-wideband antenna structure diagram

parameter Parameter value (mm) parameter Parameter value (mm) L ₁₁ 5.00 W ₁₁ 0.50 L ₁₂ 3.54 W ₁₂ 0.50 L ₃₁ 3.31 W ₃₁ 1.00 L ₃₂ 0.58 W ₃₂ 1.00 L ₄ 3.00 W ₄ 0.82 L ₅ 14.55 W ₅ 2.00 L ₆ 13.46 W ₆ 11.15 L ₇ 34.00 W ₇ 26.00 h ₇ 1.60 H ₃₁ 6.00 R _outside 9.50 _inside R 5.91 h ₆ 0.0018

The UWB antenna designed from the parameters in Table 1 is simulated by HFSS to obtain the VSWR, gain, and far-field radiation patterns of the E-plane and H-plane, as shown in Figures 5, 6 and 7, respectively.

It can be seen from Figure 5 that the standing wave ratio of the ultra-wideband antenna is greater than 2 at 5.1-5.8GHz, and the standing-wave ratio is less than 2 in the remaining frequency bands of 3.0-11.0GHz, so the ultra-wideband antenna has a band-stop characteristic at 5.1-5.8GHz .

It can be seen from Fig. 6 that the UWB antenna has good and gentle gain at all frequencies except the stopband frequency range of 5.1-5.8GHz, and the gain at 5.4GHz in the stopband frequency range drops significantly.

In Fig. 7A, Fig. 7B, Fig. 8A, Fig. 8B, Fig. 9A, Fig. 9B, Fig. 10A, and Fig. 10B, when the ultra-wideband antenna operates at 5, 5.4, 6 and 7 GHz, the corresponding E plane and H plane Far-field radiation patterns for main and cross-polarization. It can be seen from the figure that at these operating frequencies, the radiation pattern of the H plane of the antenna is omnidirectional radiation, and the radiation pattern of the E plane of the antenna is bidirectional radiation. Since 5.4GHz is in the stopband frequency band, the gain of the pattern in Fig. 8A and Fig. 8B is obviously lower than the gain of the pattern in Fig. 7A, Fig. 7B, Fig. 9A, Fig. 9B, Fig. 10A and Fig. 10B.

It can be seen from the simulation diagrams of Fig. 5, 6 and 7-10 that the antenna of the present invention meets the performance index of an ultra-wideband antenna with band-stop characteristics, and has an obvious 5.1-5.8 GHz stop-band within the 3.0-11.0 GHz ultra-broadband pass-band.

Claims (2)

1. An ultra-wideband antenna with a T-shaped structure and a matching stub with band-rejection characteristics, the ultra-wideband antenna includes a structural band, a matching stub, a ring radiator (2), a microstrip feeder (5), and a left Coplanar metal plate (61), right coplanar metal plate (62) and dielectric substrate (7); The microstrip feeder (5) is connected below the outside of the ring radiator (2); The left coplanar metal plate (61) is located on the left side of the microstrip feeder (5); The right coplanar metal plate (62) is located on the right side of the microstrip feeder (5); It is characterized in that: the structural belt is a T-shaped structural belt (1); the matching branches include a first rectangular matching branch (31), a second rectangular matching branch (32), a third rectangular matching branch (33) and a transition match stub(4); The T-shaped structural belt (1) is located in the circular radiator (2); The first rectangular matching stub (31) is located on the left side outside the circular radiator (2); The second rectangular matching branch (32) is located above the outside of the circular radiator (2); The third rectangular matching branch (33) is located on the right outside the circular radiator (2); T-shaped structural belt (1), circular radiator (2), first rectangular matching branch (31), second rectangular matching branch (32), third rectangular matching branch (33), transitional matching branch (4), The microstrip feeder (5), the left coplanar metal plate (61) and the right coplanar metal plate (62) are etched on the dielectric substrate (7) for clad copper; The T-shaped structure strip (1) is embedded in the circular radiator (2), and can provide a band stop of 5.1GHz to 5.8GHz within the passband of the antenna; The annular radiator (2) is connected to the front end of the microstrip feeder (5), and the annular structure changes the path of the surface current of the antenna, so that the energy of the antenna can be radiated outward more effectively, providing the antenna with 3.0GHz-11.0 GHz ultra wideband bandwidth; The dielectric substrate (7) adopts FR4 material with a dielectric constant of 4.4 and a loss tangent of 0.02; In order to realize the integration with the active circuit, the structure of the ultra-wideband antenna with band-rejection characteristics with a T-shaped structure and matching stubs satisfies the size relationship as follows: The length of L ₁₁ + L ₁₂ in the T-shaped structural belt (1) increases from 7.9mm to 9.9mm; L ₁₁ indicates the transverse length of the T-shaped structural belt (1), and L ₁₂ indicates the longitudinal length of the T-shaped structural belt (1) ; The inner radius R _of the circular radiator (2) is increased from 5.2mm to 7.2mm; The length L ₃₁ of the first rectangular matching stub (31) is increased from 1.9mm to 3.5mm. 2. the UWB antenna with T-shaped structure and matching stubs with band-stop characteristics according to claim 1, characterized in that: the designed UWB antenna with T-shaped structures and matching stubs with band-stop characteristics , the VSWR at 5.1-5.8GHz is greater than 2, while the VSWR in the remaining frequency bands of 3.0-11.0GHz is less than 2, so the ultra-wideband antenna has a band-stop characteristic at 5.1-5.8GHz.