阅读说明：本技术 一种加载引向器的Vivaldi天线 (Vivaldi antenna of loading director ) 是由 安文星 王双双 罗宇 马凯学 于 2021-09-16 设计创作，主要内容包括：本发明公开了一种加载引向器的Vivaldi天线,包括辐射结构、馈电结构和引向器结构；辐射结构,包括在纵向分布的上层金属接地板的前端和中部,通过刻蚀形成的缝隙结构；馈电结构,包括金属微带线和矩形结构；金属微带线,设置于上层金属接地板的底面；金属微带线的前端,与一个矩形结构相连接；引向器结构,包括相互连接的两个新型引向器；两个新型引向器前后间隔分布；两个新型引向器,位于缝隙结构的正后方。本发明的Vivaldi天线,通过将引向器加入Vivaldi天线的设计中,可以有效提高Vivaldi天线的增益,使其具备了较高的增益性能,具备增益稳定、剖面低的优秀性能,可以稳定、可靠地接收和发射无线信号。(The invention discloses a Vivaldi antenna loaded with a director, which comprises a radiation structure, a feed structure and a director structure; the radiation structure comprises a gap structure formed by etching at the front end and the middle part of the upper metal grounding plate which are longitudinally distributed; the feed structure comprises a metal microstrip line and a rectangular structure; the metal microstrip line is arranged on the bottom surface of the upper metal grounding plate; the front end of the metal microstrip line is connected with a rectangular structure; the guider structure comprises two novel guiders which are connected with each other; the two novel directors are distributed at intervals from front to back; two novel directors are positioned right behind the gap structure. The Vivaldi antenna of the invention can effectively improve the gain of the Vivaldi antenna by adding the director into the design of the Vivaldi antenna, so that the Vivaldi antenna has higher gain performance, excellent performances of stable gain and low section, and can stably and reliably receive and transmit wireless signals.)

1. A director-loaded Vivaldi antenna comprising a radiating structure, a feed structure and a director structure;

the radiation structure comprises a gap structure (10) formed by etching at the front end and the middle part of an upper-layer metal grounding plate (1) which is longitudinally distributed;

the feed structure comprises a metal microstrip line (3) and a rectangular structure (30);

the metal microstrip line (3) is arranged on the bottom surface of the upper metal grounding plate (1);

the front end of the metal microstrip line (3) is connected with a rectangular structure (30);

wherein, the guider structure comprises two novel guiders (2) which are connected with each other;

the two novel directors (2) are distributed at intervals from front to back;

two novel directors (2) are positioned right behind the gap structure (10).

2. A Vivaldi antenna loaded with director according to claim 1, characterized in that the slot structure (10), in particular, comprises: the circular gap (11), the gradual change gap (12), the rectangular gap (13) and the trapezoidal gap (14) are sequentially connected from front to back;

the central points of the circular gap (11), the gradual change gap (12), the rectangular gap (13) and the trapezoidal gap (14) are positioned on the same longitudinal axis.

3. A Vivaldi antenna loaded director according to claim 2, characterized in that the circular slot (11) is circular in shape with a radius of (30) mm.

4. A director-loaded Vivaldi antenna according to claim 2, characterized in that the metal microstrip line (3) comprises: a longitudinal wire (31) and a transverse wire (32);

the rectangular structure (30) is a rectangular notch groove which is arranged at the front end of the upper-layer metal grounding plate (1), is provided with an opening at the front side and is provided with openings at the upper side and the lower side;

one end of the longitudinal metal wire (31) is vertically connected with the rear end of the rectangular structure (30);

the other end of the longitudinal metal wire (31) is vertically connected with one end of the transverse metal wire (32);

and the transverse metal wire (32) is perpendicularly intersected with the longitudinal axis where the central points of the circular gap (11), the gradual change gap (12), the rectangular gap (13) and the trapezoidal gap (14) are located.

5. A director-loaded Vivaldi antenna according to claim 1, wherein the bottom surface of the slot structure (10) is spaced from the top surface of the metal microstrip line (3) by a predetermined distance in the vertical direction.

6. A Vivaldi antenna loaded with directors as claimed in claim 5, wherein the preset distance value is 1 mm.

7. A director-loaded Vivaldi antenna according to claim 2, characterized in that each new director (2) comprises two director metal blocks (21);

two director metal blocks (21) which are arranged at the left end and the right end of the rear side of the upper layer metal grounding plate (1) in a left-right symmetrical manner;

an auxiliary rectangular metal matrix combination (22) is arranged on the rear top surface of the upper metal grounding plate (1) at the rear position of the gap between the two director metal blocks (21).

8. A Vivaldi antenna loaded with directors as claimed in claim 7, wherein the director metal block (21) is an L-shaped metal block;

an auxiliary rectangular metal array combination (22) which comprises two rows of metal blocks which are distributed at intervals in the transverse direction;

each column of metal blocks comprises a plurality of preset rectangular metal blocks which are longitudinally distributed at intervals.

9. A director-loaded Vivaldi antenna according to claim 2, characterized in that between the front end of the new director (2) located in front and the rear edge line of the trapezoidal slot (14), there is a first gap (5) distributed laterally;

and a second gap (6) which is transversely distributed is arranged between the rear ends of the two director metal blocks (21) in the front novel director (2) and the front ends of the two director metal blocks (21) in the rear novel director (2).

Technical Field

The invention relates to the technical field of antennas, in particular to a Vivaldi antenna loaded with a director.

Background

At present, the development of modern wireless communication technology is promoted by continuous innovation of scientific technology, and an antenna is used as an important device of a communication system and puts higher requirements on the performance of the antenna.

Broadband, high gain, good directivity, and low cost, easily integrated antennas are receiving increasing attention.

The Vivaldi antenna (i.e., slotted antenna) is an end-fire tapered slot antenna, and the current distribution is mainly concentrated near the slot line which changes exponentially, so that the Vivaldi antenna has good broadband performance and is widely applied to communication.

However, for the conventional Vivaldi antenna, the radiation gain and directivity of the antenna are to be further improved.

Disclosure of Invention

The invention aims to provide a Vivaldi antenna loaded with a director, aiming at the technical defects in the prior art.

To this end, the invention provides a Vivaldi antenna loaded with a director, comprising a radiating structure, a feed structure and a director structure;

the radiation structure comprises a gap structure formed by etching at the front end and the middle part of an upper metal grounding plate which is longitudinally distributed;

the feed structure comprises a metal microstrip line and a rectangular structure;

the metal microstrip line is arranged on the bottom surface of the upper metal grounding plate;

the front end of the metal microstrip line is connected with a rectangular structure;

the guider structure comprises two novel guiders which are connected with each other;

the two novel directors are distributed at intervals from front to back;

two novel directors are positioned right behind the gap structure.

Preferably, the slit structure specifically includes: the circular gap, the gradual change gap, the rectangular gap and the trapezoidal gap are sequentially connected from front to back;

the central points of the circular gap, the gradual change gap, the rectangular gap and the trapezoidal gap are positioned on the same longitudinal axis.

Preferably, the circular slit is circular in shape with a radius of millimeters.

Preferably, the metal microstrip line includes: a longitudinal metal wire and a transverse metal wire;

the rectangular structure is a rectangular notch groove which is arranged at the front end of the upper-layer metal grounding plate, is provided with a front-side opening and is provided with openings at the upper side and the lower side;

one end of the longitudinal metal wire is vertically connected with the rear end of the rectangular structure;

the other end of the longitudinal metal wire is vertically connected with one end of the transverse metal wire;

and the transverse metal wire is vertically crossed with the longitudinal axis where the central points of the circular gap, the gradual change gap, the rectangular gap and the trapezoidal gap are located.

Preferably, the bottom surface of the slot structure and the top surface of the metal microstrip line have a preset distance in the vertical direction.

Preferably, the preset distance value is 1 mm.

Preferably, each novel director comprises two director metal blocks;

the two director metal blocks are arranged at the left end and the right end of the rear side of the upper layer metal grounding plate in a left-right symmetrical mode;

and an auxiliary rectangular metal array combination is arranged on the rear top surface of the upper metal grounding plate and at the rear position of the gap between the two director metal blocks.

Preferably, the director metal block is an L-shaped metal block;

the auxiliary rectangular metal array combination comprises two rows of metal blocks which are transversely distributed at intervals;

each column of metal blocks comprises a plurality of preset rectangular metal blocks which are longitudinally distributed at intervals.

Preferably, a first gap which is transversely distributed is arranged between the front end of the novel guider positioned at the front and the rear side edge line of the trapezoidal gap;

the rear ends of the two director metal blocks in the front novel director and the front ends of the two director metal blocks in the rear novel director are provided with second gaps which are transversely distributed.

Compared with the prior art, the Vivaldi antenna loaded with the director has the advantages that the structural design is scientific, and under the condition of the same antenna main body structure, the gain of the Vivaldi antenna can be effectively improved by adding the director into the design of the Vivaldi antenna, so that the Vivaldi antenna has higher gain performance.

Through inspection, the Vivaldi antenna of the loading director provided by the invention has the excellent performances of stable gain and low section, and can stably and reliably receive and transmit wireless signals.

Drawings

FIG. 1 is a top view of an upper metal ground plate in a Vivaldi antenna loaded with directors according to the present invention;

fig. 2 is a schematic view of a three-dimensional connection structure of an upper metal ground plate, a feed structure and a novel director in a Vivaldi antenna loaded with a director according to the present invention;

fig. 3 is a schematic diagram of a three-dimensional connection structure of an upper metal ground plate, a feed structure and a conventional director in a Vivaldi antenna loaded with a director according to the present invention;

FIG. 4 is a comparison graph of analog relative bandwidth matching for a Vivaldi antenna loaded with directors according to the present invention;

FIG. 5 is a graph of gain comparison obtained from simulation of a Vivaldi antenna loaded with directors according to the present invention;

FIG. 6a is a Vivaldi antenna loaded with directors according to the present invention, which simulates E-plane (i.e. electrical plane, i.e. the plane of the direction parallel to the direction of the electric field) radiation pattern of the antenna obtained by simulation;

FIG. 6b is a Vivaldi antenna loaded with directors according to the present invention, which simulates H-plane (i.e. magnetic plane, i.e. the plane of the direction parallel to the direction of the magnetic field) radiation pattern of the antenna obtained by simulation;

wherein: 1. an upper metal ground plate; 2. a novel director; 3. a metal microstrip line; 4. a conventional director.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the following embodiments of the present invention, and it should be understood that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on those shown in the drawings, and are used only for convenience in describing the present invention and for simplicity in description, and do not indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and thus, are not to be construed as limiting the present invention. Furthermore, the terms "first", "second", etc. are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first," "second," etc. may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless otherwise specified.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art through specific situations.

The present invention will be described in detail below with reference to the embodiments with reference to the attached drawings.

Referring to fig. 1 to 6, the present invention provides a Vivaldi antenna loaded with a director, whose operating frequency band can cover 190MHz to 280MHz, and the antenna specifically includes a radiation structure, a feed structure and a director structure;

the radiation structure comprises a gap structure 10 formed by etching at the front end and the middle part of an upper-layer metal grounding plate 1 which is longitudinally distributed;

the feed structure comprises a metal microstrip line 3;

the metal microstrip line 3 is arranged on the bottom surface of the upper metal grounding plate 1;

the front end of the metal microstrip line 3 is connected with a rectangular structure 30.

The guider structure comprises two novel guiders 2 which are connected with each other;

the two novel directors 2 are distributed at intervals from front to back;

two novel directors 2 are located directly behind the slot structure 10.

In the present invention, in a specific implementation, the peripheral edge lines of the slit structure 10 are groove lines;

the gap structure 10 specifically includes: the device comprises a circular gap 11, a gradual change gap 12, a rectangular gap 13 and a trapezoidal gap 14 which are sequentially connected from front to back;

the central points of the circular slit 11, the gradual change slit 12, the rectangular slit 13 and the trapezoidal slit 14 are located on the same longitudinal axis.

In particular, the slot lines (i.e., the peripheral edge lines of the slot structure 10) include the circular slot line at the bottom and the rectangular slot line in the middle (the peripheral edge line of the rectangular slot 13) and the gradual change slot line (i.e., the peripheral edge line of the gradual change slot 12).

In a specific implementation, the circular slit 11 is circular and has a radius of 30 mm.

In the present invention, in a specific implementation, the metal microstrip line 3 includes: longitudinal metal lines 31 and transverse metal lines 32;

the rectangular structure 30 is a rectangular notch groove which is arranged at the front end of the upper-layer metal grounding plate 1, is provided with an opening at the front side and is provided with openings at the upper side and the lower side;

one end of the longitudinal metal wire 31 is vertically connected with the rear end of the rectangular structure 30;

the other end of the longitudinal metal wire 31 is vertically connected with one end of the transverse metal wire 32;

the transverse metal wire 32 perpendicularly intersects the longitudinal axes of the center points of the circular slit 11, the gradual change slit 12, the rectangular slit 13, and the trapezoidal slit 14.

In this invention, in a specific implementation, the gap between the radiation structure and the feeder structure is a preset value (preferably 1 mm), specifically: the bottom surface of the slot structure 10 is spaced from the top surface of the metal microstrip line 3 by a predetermined distance (preferably 1 mm) in the vertical direction.

It should be noted that, with the antenna of the present invention, when the antenna is in operation, the metal microstrip line 3 is fed by coupling energy to the slot line (i.e., the peripheral edge line of the slot structure 10). The radiation arm is divided into two parts, rectangular slot line (being the edge line all around of rectangular gap 13) part and exponential curve gradual change part (being the edge line part all around of gradual change gap 12), and rectangular slot line part is inside the energy constraint slot line, mainly used transmission energy, and along with gradual change part opening width is bigger and bigger, when the slot line width is greater than one-half of corresponding frequency channel wavelength, the energy will break loose and tie and outwards radiate, and gradual change part's effect is mainly radiant energy.

Vivaldi's formula for the tapered slot line (i.e., the peripheral edge line of the tapered slot 12):

for the content of the above Vivaldi's gradient slot line formula, reference may be made to the article "li, luzhong zhi, boji, sun-fenglin [ M ], recorded in 2008, publication No. 06.

In the above formula, the Y function, formula (1), is an exponential function of the slotline, C₁And C₂To refer to the coefficients, (x)₁,y₁),(x₂,y₂) The coordinates of the beginning and the end of the progressive groove line are respectively, R is the curvature of the progressive groove line, the bending degree of the groove line is determined, and the progressive groove line becomes a straight line when R is 0. The widths of the starting end and the tail end of the slot line are related to the Vivaldi working frequency band, theoretically, the Vivaldi antenna generates radiation under the condition that the width of the opening of the slot line is greater than one half wavelength of the corresponding frequency and less than two times of the wavelength, the maximum width of the tail end of the gradual change slot line depends on the low-frequency cut-off frequency, and the minimum width of the starting end depends on the high-frequency cut-off frequency. Through the optimization of the antenna matching and the gain performance, in the invention, the antenna slot adopts a circular slot 11, a gradual change slot 12, a rectangular slot 13 and a trapezoidal slot 14 which are sequentially connected from front to back.

In the present invention, the extended portion of the lower end of the slot line is designed as a circular resonator structure (i.e., a circular slot 11), which can ensure that the end of the slot line remains short-circuited in a wider frequency band. When energy is coupled to the slot line through the microstrip line, a part of the energy is transmitted along the main radiation direction, the other part of the energy is transmitted along the direction opposite to the main radiation direction of the antenna, the circular slot 11 is used for reflecting the part of the energy to the main radiation direction of the antenna, the radius parameter of the circular slot 11 plays an impedance matching role on the microstrip transmission line through simulation, and the best matching is obtained by selecting the radius of 30 mm through simulation optimization.

In the invention, the selection of the antenna dielectric plate has great influence on the antenna performance, and when the thickness of the antenna dielectric plate is thicker, the bandwidth can be widened, but when the dielectric substrate is too thick, the surface wave effect can be excited, secondary radiation formed by the surface wave is disordered, so that the gain of the antenna is reduced, the secondary lobe of a directional diagram is increased, and the performance is deteriorated. In the design process of the antenna, the height between the radiation structure and the feeder line is selected to be 1 mm on the basis of keeping the gain performance of the antenna, and the design process specifically comprises the following steps: the bottom surface of the slot structure 10 is spaced from the top surface of the metal microstrip line 3 by a predetermined distance (preferably 1 mm) in the vertical direction.

In the present invention, in a specific implementation, each new director 2 comprises two director metal blocks 21;

two director metal blocks 21 which are arranged at the left end and the right end of the top part of the back side of the upper layer metal earth plate 1 in a left-right symmetry manner;

the rear top surface of the upper metal earth plate 1 is provided with an auxiliary rectangular metal matrix assembly 22 at the rear position of the gap between the two director metal blocks 21.

In particular, the deflector metal block 21 is preferably an L-shaped metal block.

In particular, the auxiliary rectangular metal array combination 22 comprises two rows of metal blocks which are transversely distributed at intervals;

each column of metal blocks comprises a plurality of preset rectangular metal blocks (not limited to six metal blocks shown in fig. 1) which are longitudinally distributed at intervals.

In the invention, in the concrete implementation, a first gap 5 which is transversely distributed is arranged between the front end of the novel guider 2 positioned in front and the rear side edge line of the trapezoidal gap 14;

the two rear ends of the metal block 21 of the front novel director 2 and the two front ends of the metal block 21 of the rear novel director 2 have second gaps 6 distributed transversely.

For the invention, it should be noted that the invention adopts a slot coupling feed form to realize an impedance matching design, and the antenna mainly comprises an upper layer metal ground plate 1 positioned at the topmost layer, a slot structure 10 surrounded by slot lines etched on the upper layer metal ground plate 1, a metal microstrip line 3 positioned at the bottommost layer and a novel director 2;

the upper metal grounding plate 1 main body at the topmost layer is a rectangle with an etched gap and is also a main radiation structure;

wherein, the gap of upper strata metal ground plate 1 upper etching mainly includes: a circular slit 11, a tapered slit 12, a rectangular slit 13, and a trapezoidal slit 14. The circular slot 11 mainly plays a role in impedance matching of the microstrip transmission line (namely the metal microstrip line 3); the gradual change gap 12 connected with the circular gap 11 and the microstrip transmission line (namely the metal microstrip line 3) play a role of mutually coupling electromagnetic waves; the rectangular slot 13 and the trapezoidal slot 14 play a certain guiding role for the electromagnetic wave radiated by the antenna;

the metal microstrip line 3 is positioned at the bottommost layer, and the terminal of the metal microstrip line is of an auxiliary rectangular structure and mainly plays a role in matching terminal loads.

In particular, for the Vivaldi antenna, the director structure can adopt not only the novel director 2 shown in fig. 1 and 3, but also the conventional director 4 shown in fig. 3;

a conventional director 4 comprising two rows of laterally spaced apart metal blocks;

each column of metal blocks comprises a plurality of preset rectangular metal blocks (not limited to the thirteen metal blocks shown in fig. 3) which are longitudinally distributed at intervals.

It should be noted that the rectangular metal block of the conventional director 4 is also disposed on a metal base plate of the director.

In the present invention, for the Vivaldi antenna provided by the present invention, when it works, energy is coupled to the slot line, i.e. the slot structure 10, through the metal microstrip line 3, and then flows along the beginning end of the tapered slot line toward the end opening direction of the slot line, the Vivaldi antenna is a traveling wave antenna with end-fire characteristics. According to the radiation principle of Vivaldi antenna, when the width of the slot line is more than one half wavelength of the working frequency and less than two times wavelength, the antenna can generate effective radiation.

In the invention, the upper layer metal structure (namely the upper layer metal ground plate 1), the novel director 2 and the feed structure (namely the metal microstrip line 3) of the antenna are required to be metal copper materials, and are all single-layer structures. When the antenna works, the metal microstrip line 3 couples energy to the upper metal structure 1 through the gap 10, the energy is transmitted on the upper metal structure 1, the energy radiates outwards through the open gap 10, and the energy radiates to the director 2.

In the present invention, the gap structure 10 and the metal ground plate structure (i.e., the upper metal ground plate 1) are coplanar and have a single-layer structure, and the gap structure 10 is substantially formed by etching a circular gap 11, a tapered gap 12, a rectangular gap 13, a trapezoidal gap 14, and the like on the metal ground plate. In the antenna, the loading of the slot structure 10 mainly functions to transmit energy, and the gain of the antenna and the radiation stability of the antenna can be effectively improved by properly adjusting the slot structure.

In the present invention, the rectangular structure 30 is a rectangular slot etched on the same plane of the metal ground plate (i.e. the upper metal ground plate 1), and is mainly used for facilitating a gap reserved when the microstrip line is externally connected with the SMA connector.

In the present invention, the longitudinal metal line 31 and the transverse metal line 32 included in the metal microstrip line 3 are made of a metal copper material and have a single-layer structure. The longitudinal metal wire 31 and the transverse metal wire 32 of the metal microstrip line are mainly used for adjusting impedance matching of the antenna, the longitudinal metal wire 31 is used for transferring energy, and the transverse metal wire 32 can couple the energy to the upper metal ground plate 1 through a gap etched on the upper metal ground plate 1 to realize radiation of the antenna.

In the present invention, the director metal block 21 and the attached rectangular metal matrix assembly 22 in the director structure are both made of ideal metal copper material, and are of single-layer structure, and are coplanar with the metal grounding plate structure (i.e. the upper metal grounding plate). The guiding metal block 21 in the director structure is mainly used for further superposing the energy radiated by the antenna, so that the directivity and the gain of the antenna are enhanced, and meanwhile, the auxiliary rectangular metal array combination 22 is loaded, so that the directivity of the antenna can be further enhanced, and the antenna has higher gain performance.

In the invention, the director metal blocks 21 of the two novel directors 2, the auxiliary rectangular metal array combination 22 and the upper-layer metal grounding plate 1 are in the same plane, and the processing mode adopted is a printing mode.

In the invention, the first gap 5 and the second gap 6 are used for adjusting the phase difference between the director and the antenna, and the two gaps are properly adjusted, so that the director can achieve the maximum directing effect, and the directivity and the gain of the antenna are improved.

In the present invention, fig. 4, 5 and 6 show the radiation performance of the Vivaldi antenna of the present invention. The Vivaldi antenna designed by the invention has the advantages that the impedance matching bandwidth is 190MHz-280MHz, the relative bandwidth is 38%, a relatively stable gain is maintained in the frequency band, the simulation gain peak value is 5.96dBi, the radiation pattern accords with the characteristics of a directional antenna, the front-to-back ratio of main polarization is more than 10dB, and good directional radiation can be realized. For the antenna of the invention, the radiation energy of the E surface (electric surface, namely the direction plane parallel to the direction of the electric field) and the H surface (magnetic surface, namely the direction plane parallel to the direction of the magnetic field) of the antenna is mainly concentrated in the normal direction, thereby having better stability, and the radiation pattern keeps good directivity and can achieve better radiation performance.

Wherein, the solid line of fig. 4 shows the impedance matching performance of the antenna of the present invention (i.e. the antenna loaded with the novel director), and the dotted line shows the impedance matching performance of the loaded conventional director structure shown in fig. 3, as can be seen from fig. 4, the antenna designed by the present invention has better impedance matching performance.

The solid line of fig. 5 shows the gain performance of the antenna of the present invention (i.e., the antenna loaded with the novel director), and the dashed line shows the gain performance modeled for the loaded conventional director structure shown in fig. 3. as can be seen from fig. 5, the antenna designed by the present invention has a higher gain than the antenna loaded with the conventional director.

Fig. 6 is a directional diagram of the antenna (i.e., the antenna loaded with the novel director) designed according to the present invention, showing that the antenna has good directional performance, concentrated energy radiation, and good directivity.

Compared with the prior art, the Vivaldi antenna loaded with the director has the following beneficial effects:

1. according to the invention, the rectangular structure is loaded at the tail end of the microstrip feeder (namely the metal microstrip line 3), so that the impedance matching of the antenna is improved, and the bandwidth can cover the frequency band of 190MHz-280 MHz;

2. according to the invention, the director structure is loaded after the metal sheet (namely the radiation structure) is radiated, so that the gain of the antenna at 190MHz-280MHz is obviously improved, and the radiation stability is enhanced;

3. the antenna of the invention has scientific structural design and practical application and popularization value.

It should be noted that, for the Vivaldi antenna provided by the present invention, when the antenna operates, energy is coupled to the slot line through the microstrip line, and then flows along the beginning of the tapered slot line toward the end opening of the slot line, and the Vivaldi antenna is a traveling wave antenna with end-fire characteristics. To meet the requirement of a traveling wave mechanism, the length of the antenna meets the condition that the length of the antenna is more than or equal to lambda/2 and less than or equal to lambda, the antenna is required to work in a target frequency band of 190MHz-280MHz, and the center frequency is f₀A suitable antenna length is adjusted to about 1200 mm at 235 MHz. The microstrip antenna is a half-wave resonant antenna, the long side L of a rectangular patch is λ/2(λ is equivalent wavelength), the width W of a radiation patch directly affects the characteristics of the antenna, such as impedance bandwidth, overall size and the like, and the selection of the value is particularly important in the design of the microstrip antenna. The width W of the microstrip patch is calculated by the formula:

in the formula (4), c is the speed of light in vacuum, f₀Is the center frequency, ε, of the antenna_rIs the relative dielectric constant of the dielectric plate.

According to the invention, the introduction of the director structure is essentially the influence of the current phase, the current of the director lags behind the current on the antenna, the antenna signals are transmitted to the director part, the currents are superposed in phase, and the signal superposition is enhanced, so that the Vivaldi antenna has good radiation performance on the whole, and the gain is improved.

In summary, compared with the prior art, the Vivaldi antenna loaded with the director provided by the invention has a scientific structural design, and under the condition of the same antenna main body structure, the director is added into the design of the Vivaldi antenna, so that the gain of the Vivaldi antenna can be effectively improved, and the Vivaldi antenna has higher gain performance.

Through inspection, the Vivaldi antenna of the loading director provided by the invention has the excellent performances of stable gain and low section, and can stably and reliably receive and transmit wireless signals.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.