Vivaldi Antenna

Abstract

The present invention provides a Vivaldi antenna, comprising a dielectric plate and a radiating plate arranged on the dielectric plate, wherein a radiating slot is arranged in the middle of the radiating plate, a short-circuit cavity is arranged at one end of the radiating slot, and a composite slot is arranged at a position close to the short-circuit cavity, wherein the composite slot comprises a first slot and a second slot which are sequentially opened along a side of the radiating plate away from the radiating slot toward the middle, and the second slot is opened toward the short-circuit cavity with respect to the first slot. The Vivaldi antenna of the present invention can concentrate current on the radiating slot by arranging the composite slot, suppress the edge current on the edge of the radiating plate, improve the performance of the directional pattern, expand the low-frequency bandwidth, and also realize the miniaturization of the Vivaldi antenna.

Description

Technical Field

[0001] The invention belongs to the technical field of mobile communications, and in particular relates to a Vivaldi antenna. Background Art

[0002] With the continuous development of communication technology, the communication rate continues to increase, the unique advantages of ultra-wideband antennas are becoming increasingly prominent, and the application of antennas in some systems is becoming increasingly broadband. The research on ultra-wideband antennas has become one of the research hotspots for domestic and foreign scholars.

[0003] To this end, industry insiders proposed the Vivaldi antenna. The Vivaldi antenna has been widely used in communication and measurement systems, radar systems, biomedical detection and other fields due to its wide operating frequency band, stable gain, beam symmetry, easy integration and simple structure.

[0004] However, during the application of Vivaldi antennas, the radiation pattern is easily distorted and the energy radiation effect is not ideal, which greatly affects users during use. Summary of the invention

[0005] An object of the present invention is to solve at least one of the above problems and provide a Vivaldi antenna.

[0006] To adapt to the various purposes of the present invention, the present invention adopts the following technical solutions:

[0007] A Vivaldi antenna is provided to meet one of the purposes of the present invention, including a dielectric plate and a radiating plate arranged on the dielectric plate, wherein a radiating slot is provided in the middle of the radiating plate, a short-circuit cavity is provided at one end of the radiating slot, and a composite slot is provided at a position close to the short-circuit cavity. The composite slot includes a first slot and a second slot that are sequentially opened along a side of the radiating plate away from the radiating slot toward the middle, and the second slot is opened relative to the first slot and is bent toward the short-circuit cavity.

[0008] Furthermore, the first slot is a transverse slot, and the second slot is an oblique slot.

[0009] Furthermore, the first slot includes a first slot line and a second slot line that are parallel to each other, the second slot includes a third slot line and a fourth slot line that intersect each other, the third slot line is connected to the first slot line to form an angle of 130° to 160°, and the third slot line is connected to the fourth slot line to form an angle of 10° to 30°.

[0010] Furthermore, a plurality of matching grooves are arranged along the outer circumference of the short-circuit cavity.

[0011] Furthermore, the radiation sheet is provided with two groups of inclined grooves, the two groups of inclined grooves are symmetrically arranged with respect to the radiation groove, and the inclined grooves are inclined toward the radiation groove.

[0012] Specifically, each group of inclined slots includes a plurality of inclined slots, and the plurality of inclined slots are arranged in sequence from one end to the other end of the radiation slot, and the intervals between two adjacent inclined slots are arranged in equal intervals.

[0013] Furthermore, the radiation sheet is provided with suppression parts on both sides thereof, and the suppression parts include a plurality of suppression grooves arranged in parallel.

[0014] Furthermore, the radiation sheet is provided with an exponential gradient groove at the other end of the radiation groove.

[0015] Specifically, matching resistors are provided on both sides of the radiation slot.

[0016] Specifically, the radiation plate is arranged on the front side of the dielectric plate, the Vivaldi antenna further comprises a feeding coupling plate arranged on the back side of the dielectric plate, the feeding element comprises a feeding coupling plate, and the feeding coupling plate is coupled with the slot line of the radiation slot.

[0017] Compared with the prior art, the present invention has many advantages, including but not limited to:

[0018] The Vivaldi antenna of the present invention is provided with a composite slot, and the second slot of the composite slot is arranged toward the short-circuit cavity to guide the current on the cavity line of the short-circuit cavity to the radiation slot, so that the current converges on the radiation slot and radiates signals externally. And by providing the composite slot, the current fed into the radiation sheet is concentrated on the radiation slot, the edge current of the radiation sheet is suppressed, the radiation efficiency is improved, the radiation pattern is greatly improved, and the bandwidth can be expanded at the same time. It can also avoid increasing the area of ​​the radiation surface to reduce the edge current, and realize the miniaturization of the Vivaldi antenna.

[0019] Additional aspects and advantages of the present invention will be given in part in the following description, which will become obvious from the following description, or may be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0021] Figure 1 Schematic diagram of the structure of a Vivaldi antenna according to a typical embodiment of the present invention.

[0022] Figure 2 FIG. 4 is a schematic diagram of the back side of a Vivaldi antenna according to a typical embodiment of the present invention.

[0023] Figure 3It is a schematic structural diagram of the composite slot of the Vivaldi antenna according to a typical embodiment of the present invention.

[0024] Figure 4 It is a schematic structural diagram of the oblique slot portion of the Vivaldi antenna according to a typical embodiment of the present invention. DETAILED DESCRIPTION

[0025] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements with the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention and cannot be interpreted as limiting the present invention.

[0026] It will be understood by those skilled in the art that, unless expressly stated, the singular forms "one", "said", and "the" used herein may also include plural forms. It should be further understood that the term "comprising" used in the specification of the present invention refers to the presence of the features, integers, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or groups thereof. It should be understood that when we refer to an element as being "connected" or "coupled" to another element, it may be directly connected or coupled to the other element, or there may be an intermediate element. In addition, the "connection" or "coupling" used herein may include wireless connection or wireless coupling. The term "and / or" used herein includes all or any unit and all combinations of one or more associated listed items.

[0027] It will be understood by those skilled in the art that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as generally understood by those skilled in the art in the art to which the present invention belongs. It should also be understood that terms such as those defined in general dictionaries should be understood to have meanings consistent with the meanings in the context of the prior art, and will not be interpreted with idealized or overly formal meanings unless specifically defined as herein.

[0028] The present invention provides a Vivaldi antenna. The Vivaldi antenna expands bandwidth, reduces pattern distortion, achieves impedance matching, and improves radiation characteristics by arranging composite slots on both sides of a radiation channel.

[0029] In an exemplary embodiment of the present invention, Figure 1 The Vivaldi antenna 100 includes a dielectric plate 1, a radiation plate 40 disposed on the dielectric plate 1, and a feeding element.

[0030] The radiation sheet 40 includes four sides, which are a first side 31, a second side 32, a third side and a fourth side 34 connected in sequence, wherein the first side 31 is arranged in parallel with the third side, and the first side 31 is arranged opposite to the third side, and the second side 32 is arranged in parallel with the fourth side 34.

[0031] The radiation plate 40 is provided with a radiation channel 35, and the radiation plate 40 sequentially forms a feed matching portion 41, an intermediate transmission portion 42, and a radiation guide portion 43 along the extension direction of the radiation channel 35. The radiation channel 35 extends from the first side 31 to the third side, and the radiation channel 35 is arranged between the second side 32 and the fourth side 34.

[0032] The radiation channel 35 is a slot-shaped channel formed by hollowing out the radiation sheet 40, and includes a first radiation slot line 351 and a second radiation slot line 352, which define the slot-shaped channel. The two ends of the radiation channel 35 are a feeding end 36 and a radiation end 38, respectively.

[0033] The feeding end 36 is arranged close to the first side 31, the radiating end 38 is arranged close to the third side, and the radiating end 38 forms an exponential gradient groove 381 at the third side, and the exponential gradient groove 381 will run through the third side, thereby removing the third side on the radiation plate 40, so that the first radiation groove line 351 is connected to the fourth side 34, and the second radiation groove line 352 is connected to the second side 32.

[0034] In one embodiment, the first radiation slot line 351 and the second radiation slot line 352 are in an exponential parabola shape at the exponential gradient slot 381. The radiation slot 37 is an elongated slot connected to the exponential gradient slot 381 of the radiation end 38.

[0035] The feeding end 36 is coupled to the feeding element, and the feeding element couples and feeds current to the feeding end 36. The current fed into the feeding end 36 flows to the first radiation slot line 351 and the second radiation slot line 352 respectively. The current flowing to the first radiation slot line 351 and the second radiation slot line 352 radiates signals to the outside at the exponential gradient slot 381.

[0036] In one embodiment, part of the current may flow to the fourth side 34 through the first radiation slot line 351 , and / or flow to the second side 32 through the second radiation slot line 352 , forming an edge current.

[0037] In a typical embodiment of the present invention, the feeding end 36 is disposed on the feeding matching portion 41 of the radiation sheet 40, and the feeding end 36 is the area of ​​the radiation slot 37 close to the first side 31. The current fed into the feeding end 36 by the feeding element converges on the radiation slot 37, that is, converges on the first radiation slot line 351 and the second radiation slot line 352, so as to radiate the signal externally through the exponential gradient slot 381 of the radiation end 38.

[0038] The radiation slot 37 is also connected to the short-circuit cavity 7, which is circular and formed by a hollow radiation sheet 40. The short-circuit cavity 7 is defined by its cavity line 71, and the cavity line 71 of the short-circuit cavity 7 is connected to the first radiation slot line 351 and the second radiation slot line 352. Specifically, the short-circuit cavity 7 is connected to the radiation slot 37 formed by the first radiation slot line 351 and the second radiation slot line 352.

[0039] By providing the short-circuit cavity 7, impedance matching can be achieved over a wider frequency band, and providing the short-circuit cavity 7 can also reduce the standing wave ratio and improve radiation performance. Preferably, the radius of the short-circuit cavity 7 is 36 mm-41 mm.

[0040] A plurality of matching slots 5 are provided around the short-circuit cavity 7, and the plurality of matching slots 5 are sequentially arranged along the circumference of the circular short-circuit cavity 7, and the matching slots 5 are formed by hollowing out the radiation sheet 40. The plurality of matching slots 5 are used to achieve impedance matching over a wider frequency band to improve the radiation performance of the Vivaldi antenna 100. Preferably, the matching slots 5 are circular, and the radius thereof is 3 mm-5 mm.

[0041] In one embodiment, the feed matching part 41 is further provided with a plurality of optimization slots 6, the optimization slots 6 are formed by the hollow radiation sheet 40, and the optimization slots 6 include a first opening arranged on the first side 31 of the radiation sheet 40. The optimization slots 6 are used to change the current distribution around the short-circuit cavity 7 and optimize the standing wave ratio. Preferably, the optimization slots 6 are semi-elliptical, with a radius of 38 mm-42 mm and a curvature of 0.5-0.6.

[0042] In a typical embodiment of the present invention, a pair of composite slots 4 are provided on the feed matching portion 41, and the composite slots 4 are formed by hollowing out the radiation sheet 40. The pair of composite slots 4 are arranged close to the intermediate transmission portion 42, the pair of composite slots 4 are arranged on both sides of the radiation slot 37, and the pair of composite slots 4 are symmetrically structured with respect to the radiation slot 37.

[0043] Combination Figure 3The composite groove 4 includes a first groove 80 and a second groove 14, and the first groove 80 is connected to the second groove 14. The first groove 80 includes a second opening 11 arranged on the fourth side 34, and the second opening 11 divides the fourth side 34 into two. The first groove 80 includes a first groove line 12 and a second groove line 15 that are parallel to each other, and the first groove line 12 and the second groove line 15 define the first groove 80 in a rectangular groove shape, and one end of each of the first groove line 12 and the second groove line 15 is arranged on the fourth side 34. Moreover, the first groove line 12 and the second groove line 15 are both perpendicular to the radiation groove 37, that is, the first groove 80 is perpendicular to the radiation groove 37. The first groove 80 extends from the fourth side 34 to the radiation groove 37 or the second side 32. In one embodiment, the first groove 80 is a transverse groove, and the second groove 14 is an oblique groove.

[0044] The second slot 14 includes a third slot line 13 and a fourth slot line 60, and the third slot line 13 and the fourth slot line 60 are arranged to intersect to define a triangular second slot 14. The third slot line 13 is connected to the first slot line 12, and the fourth slot line 60 is connected to the second slot line 15, so as to define the composite slot 4. Preferably, the third slot line 13 is connected to the first slot line 12 to form an angle of 130° to 160°.

[0045] The third slot line 13 of the second slot 14 intersects with the fourth slot line 60 to form a first angle, and the first angle is oriented toward the radiation slot 37. The first angles of each of the pair of composite slots 4 are oriented toward the radiation slot 37 to guide the current on the short-circuit cavity 7 to the radiation slot 37, to avoid the current from gathering on the short-circuit cavity 7, so that the current flows through the radiation slot 37 to the exponential gradient slot 381 of the radiation end 38 for signal radiation. By providing a pair of composite slots 4, the current gathered on the short-circuit cavity 7 can be guided to the radiation slot 37 to increase the intensity of signal radiation and improve radiation performance. In one embodiment, the third slot line 13 of the second slot 14 intersects with the fourth slot line 60 to form an angle of 10° to 30°.

[0046] Combination Figure 1 , the intermediate transmission portion 42 is provided with suppression portions on the second side 32 and the fourth side 34, respectively, and the pair of suppression portions are symmetrically structured with respect to the radiation slot 37. The suppression portion includes a plurality of suppression slots 3 arranged in parallel, and the suppression slots 3 include a third opening opened on the corresponding side, and the suppression slots 3 extend from the third opening to the radiation slot 37. By arranging a plurality of parallel suppression slots 3 on the suppression portion, the edge current flowing into the second side 32 and the fourth side 34 through the exponential gradient slot 381 can be suppressed, the impedance matching can be improved, and the radiation performance can be optimized. In one embodiment, the plurality of suppression slots 3 of the suppression portion are wavy or square wave shaped.

[0047] Combination Figure 1 and Figure 4 The radiation guide portion 43 is provided with an oblique groove portion 2 on the second side 32 and the fourth side 34, respectively, and the two oblique groove portions 2 are symmetrically structured with respect to the radiation slot 37. The oblique groove portion 2 includes a plurality of oblique grooves 20, and the oblique grooves 20 include a fourth opening 21 opened on the corresponding side, and the oblique grooves 20 are arranged obliquely downward from the fourth opening 21 toward the radiation slot 37. In one embodiment, the length of the oblique groove 20 is one quarter of the working wavelength of the Vivaldi antenna 100, and the width of the oblique groove 20 is 3 mm-7 mm. Moreover, the angle 19 between the oblique groove 20 and the first side 31 is 30°-50°.

[0048] The multiple inclined grooves 20 of the inclined groove portion 2 are arranged in sequence from top to bottom (the direction from top to bottom refers to the direction from the third side toward the first side 31), and the spacing between two adjacent inclined grooves 20 gradually increases from top to bottom. In one embodiment, in the inclined groove portion 2, the spacing between two adjacent inclined grooves 20 is equidistantly distributed from top to bottom. In one embodiment, in the equidistant distribution, the spacing between two adjacent inclined grooves 20 increases by 5-10 mm from top to bottom. Preferably, the number of the inclined groove portions 2 is 3-5.

[0049] By providing two inclined groove portions 2 on the radiation guiding portion 43, the edge current flowing into the second side 32 and the fourth side 34 through the exponential gradient groove 381 can be suppressed, so that the Vivaldi antenna 100 does not need to extend the second side 32 and the fourth side 34 to suppress the edge current, thereby reducing the size of the Vivaldi antenna 100, and also improving the directional pattern characteristics and enhancing the radiation performance.

[0050] Combination Figure 2 , the feeding element is used to feed the feeding end 36 of the radiation channel 35, the feeding element is arranged on the reverse side 52 of the dielectric plate 1, and the radiation plate 40 is arranged on the front side 51 of the dielectric plate 1. The feeding element includes a feeding coupling plate 18, a feeding line 17 and a cable interface 16, the cable interface 16 is used to connect with an external cable, and the cable interface 16 is also connected to the feeding line 17, and the feeding line 17 is connected to the feeding coupling plate 18. The feeding coupling plate 18 corresponds to the position of the radiation slot 37, so as to facilitate coupling and feeding the radiation slot 37, and couple the current fed by the external cable to the radiation slot 37, and radiate the signal to the outside through the first radiation slot line 351 and the second radiation slot line 352. Preferably, the reverse side 52 of the dielectric plate 1 is a ground layer. The feeding line 17 is formed by connecting a plurality of microstrip lines.

[0051] In one embodiment, the feed coupling plate 18 is a fan-shaped open-circuit cavity to reduce energy reflection and achieve broadband impedance matching. The cable interface 16 is a coaxial cable interface, and the external cable is a coaxial cable, so that the coaxial cable is connected through the coaxial cable interface.

[0052] In one embodiment, the radiation sheet 40 is a metal sheet.

[0053] In one embodiment, the first radiation slot line 351 and the second radiation slot line 352 of the radiation channel 35, the cavity line 71 of the short-circuit cavity 7, the first side 31, the second side 32 and the fourth side 34 of the radiation plate 40 are all side walls at corresponding positions.

[0054] In one embodiment, a first matching resistor 9 is provided between the feed matching part 41 and the intermediate transmission part 42, and a second matching resistor 10 is provided between the intermediate transmission part 42 and the radiation guiding part 43. The first matching resistor 9 and the second matching resistor 10 are used for loading impedance, suppressing reflected current in the low frequency band, and expanding the low frequency bandwidth. Preferably, the first matching resistor 9 and the second matching resistor 10 are chip resistors.

[0055] In one embodiment, the dielectric constant of the dielectric plate 1 is 4.4. Using a dielectric with a high dielectric constant can reduce the wavelength of the electromagnetic wave and the size of the Vivaldi antenna 100 to achieve the goal of miniaturization.

[0056] In summary, the Vivaldi antenna of the present invention can concentrate the current on the radiation channel by setting a composite slot and two groups of oblique slots, suppress the edge current on the edge of the radiation plate, improve the radiation pattern performance, expand the low-frequency bandwidth, and also realize the miniaturization of the Vivaldi antenna.

[0057] The above description is only a preferred embodiment of the present invention and an explanation of the technical principles used. Those skilled in the art should understand that the scope of the invention involved in the present invention is not limited to the technical solution formed by a specific combination of the above technical features, but should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the above inventive concept. For example, the above features are replaced with the technical features with similar functions invented in the present invention (but not limited to) to form a technical solution.

[0058] Although the subject matter has been described in language specific to structural features and / or methodological logical actions, it should be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or actions described above. On the contrary, the specific features and actions described above are merely example forms of implementing the claims.

Claims

1. A Vivaldi antenna, Features: The invention comprises a dielectric plate and a radiation sheet arranged on the dielectric plate, wherein a radiation slot is arranged in the middle of the radiation sheet, a short-circuit cavity is arranged at one end of the radiation slot, a composite slot is arranged at a position close to the short-circuit cavity, the composite slot comprises a first slot and a second slot which are sequentially opened along a side of the radiation sheet away from the radiation slot toward the middle, and the second slot is opened toward the short-circuit cavity in a folded manner relative to the first slot; The first slot is a transverse slot, the second slot is an oblique slot, the first slot includes a first slot line and a second slot line that are parallel to each other, the second slot includes a third slot line and a fourth slot line that intersect each other, the third slot line is connected to the first slot line to form an angle of 130° to 160°, and the third slot line is connected to the fourth slot line to form an angle of 10° to 30°; The radiation sheet is provided with a pair of composite grooves, the pair of composite grooves are arranged on both sides of the radiation groove, and the pair of composite grooves are symmetrically structured with respect to the radiation groove.

2. The Vivaldi antenna according to claim 1, It is characterized in that A plurality of matching grooves are arranged along the outer circumference of the short-circuit cavity.

3. The Vivaldi antenna according to claim 1, It is characterized in that The radiation sheet is also provided with two groups of inclined grooves, which are symmetrically arranged with respect to the radiation groove, and the inclined grooves are arranged inclined toward the radiation groove.

4. The Vivaldi antenna according to claim 3, It is characterized in that Each group of inclined slots includes a plurality of inclined slots, which are arranged in sequence from one end of the radiation slot to the other end, and the intervals between two adjacent inclined slots are arranged in equal intervals.

5. The Vivaldi antenna according to claim 1, It is characterized in that The radiation sheet is provided with a suppression portion at both sides thereof, and the suppression portion includes a plurality of suppression grooves arranged in parallel.

6. The Vivaldi antenna according to claim 1, It is characterized in that The radiation sheet is provided with an exponential gradient groove at the other end of the radiation groove.

7. The Vivaldi antenna according to claim 1, It is characterized in that Matching resistors are arranged on both sides of the radiation slot.

8. The Vivaldi antenna according to claim 1, It is characterized in that The radiation plate is arranged on the front side of the dielectric plate. The Vivaldi antenna further comprises a feeding element arranged on the back side of the dielectric plate. The feeding element comprises a feeding coupling plate, and the feeding coupling plate is coupled with the slot line of the radiation slot.

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