阅读说明：本技术 一种平面超宽带单极子天线 (Plane ultra-wideband monopole antenna ) 是由 刘楚钊 陈意钒 池淼 丁亚辉 宫正 张卉 赵兵妹 巫昆仑 刘磊 于 2021-08-30 设计创作，主要内容包括：本发明涉及一种平面单极子天线,包括：单极子辐射器,所述单极子辐射器的上部设置有多条槽线。本发明的平面单极子天线采用单极子辐射器,使其在具有宽频带的同时,保证结构简单、体积小,可以提高脑卒中检测设备的便携性。此外,该天线的定向性强,结构紧凑,且天线间互耦影响小。另外,该天线的增益较高,可在介电常数较高的耦合剂环境中工作,用于脑卒中检测。该天线在医学成像领域具有极高的应用价值。(The invention relates to a planar monopole antenna, comprising: the monopole radiator, the upper portion of monopole radiator is provided with many slot lines. The planar monopole antenna adopts the monopole radiator, so that the planar monopole antenna has a wide frequency band, ensures simple structure and small volume, and can improve the portability of the stroke detection equipment. In addition, the antenna has strong directionality, compact structure and small mutual coupling influence among the antennas. In addition, the antenna has high gain, can work in a couplant environment with high dielectric constant, and is used for detecting cerebral apoplexy. The antenna has extremely high application value in the field of medical imaging.)

1. A planar monopole antenna, comprising: the monopole radiator, the upper portion of monopole radiator is provided with many slot lines.

2. The planar monopole antenna of claim 1 wherein a plurality of said slotlines form a comb structure.

3. The planar monopole antenna according to claim 1 or 2, wherein the monopole radiator has a length of 40-60mm and a width of 10-25 mm.

4. The planar monopole antenna according to claim 3 wherein said monopole radiator has a length of 45-50mm and a width of 15-20 mm.

5. The planar monopole antenna according to claim 1 or 2, wherein the lower portion of the monopole radiator is provided with two symmetrical cut angles.

6. The planar monopole antenna of claim 1 or 2, further comprising:

a dielectric substrate;

the microstrip feeder line is arranged on the upper surface of the dielectric substrate and is connected with the lower edge of the monopole radiator;

the two metal pads are arranged on the upper surface of the dielectric substrate and symmetrically arranged on two sides of the lower part of the microstrip feeder line, and metal cylinders are arranged on the two metal pads; and

the metal floor is arranged on the lower surface of the dielectric substrate and is positioned below the microstrip feeder line, and the metal floor is connected with the metal cylinder;

wherein the monopole radiator is arranged on the upper surface of the dielectric substrate.

7. The planar monopole antenna according to claim 6, wherein said monopole radiator is rectangular with cut corners and the microstrip feed line is rectangular; the center line of the short side of the microstrip feeder line is superposed with the center line of the short side of the monopole radiator.

8. The planar monopole antenna of claim 6,

the medium substrate adopts an epoxy glass fiber cloth substrate FR-4;

the monopole radiator, the microstrip feeder, the metal pad and the metal floor are each independently aluminum, iron, tin, copper, silver, gold or platinum metal, or are each independently an alloy of any one of aluminum, iron, tin, copper, silver, gold and platinum.

9. The planar monopole antenna of claim 6, wherein said microstrip feed line and said metal pad are connected by an SMA connector.

10. A stroke detection device comprising a planar monopole antenna according to any one of claims 1-9.

Technical Field

The invention relates to the technical field of antennas and the field of medical imaging, in particular to a planar ultra-wideband monopole antenna.

Background

Stroke refers to a clinical event in the cerebrovascular context that is characterized by acute onset, rapid onset of localized or diffuse loss of brain function. Stroke is the major disease causing human death, and ranks second among all types of fatal diseases. The high morbidity and mortality of stroke pose a serious challenge to the diagnosis of stroke, and the improvement of the stroke diagnosis level is not slow enough. Currently, the mainstream diagnostic methods for stroke mainly include X-ray computed tomography (X-ray CT) and nuclear Magnetic Resonance Imaging (MRI). The X-ray CT and MRI techniques have accurate and reliable diagnosis results, but the equipment is expensive, large in size and poor in portability. The X-ray CT has radiation damage to human body during the use process and may increase the carcinogenic risk. These disadvantages make these two techniques inconvenient for use in general diagnostic situations, such as real-time diagnosis in accident sites, long-term continuous monitoring of patient's condition, and population screening. In order to solve the difficulty in diagnosing stroke under the above circumstances, a technician has conducted a search for a novel brain imaging technique.

At present, biomedical microwave near-field imaging technology is used as a novel brain imaging technology, and is beginning to be applied to the research of cerebral stroke diagnosis. The basic principle of biomedical microwave near-field imaging is that biological tissues or organs are irradiated by microwaves to generate a scattered field, and an image for displaying the dielectric constant characteristics of an irradiated object is reconstructed by detecting echo signals. The ultra-wideband planar microwave antenna is used as a simple ultra-wideband signal receiving and transmitting system and is key hardware of an imaging system.

The prior art discloses a printed monopole patch antenna having dimensions of 30 x 34mm². By optimizing the partial ground layer and the added stub, good impedance matching can be achieved over a wide range (3-7GHz band). However, the antenna structure is loaded with the stub, so that the size is increased, and the complexity of the structure is also increased.

The prior art also discloses an ultra wide band microstrip monopole antenna operating in the UHF band. The antenna consists of a semicircular radiator. The antenna widens the bandwidth by etching three different equilateral hexagon complementary split ring resonators on the grounding layer below the transmission line. However, the antenna has a complex structure and requires high processing precision. In addition, the antenna has a low gain and the working environment is often air, which cannot work in the high dielectric constant couplant environment of medical imaging applications.

The above prior arts all have a problem of increasing the size or structural complexity of the antenna in order to widen the bandwidth.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provide a planar monopole antenna, which adopts a monopole radiator, ensures simple structure and small volume while having wide frequency band and can improve the portability of stroke detection equipment.

In order to achieve the above object, the present invention provides the following technical solutions.

A planar monopole antenna comprising: the monopole radiator, the upper portion of monopole radiator is provided with many slot lines.

The invention also provides equipment for detecting stroke, which comprises the planar monopole antenna.

Compared with the prior art, the invention has the beneficial effects that:

1. the planar monopole antenna adopts the monopole radiator, so that the planar monopole antenna has a wide frequency band, ensures simple structure and small volume, and can improve the portability of the stroke detection equipment.

In addition, the antenna has strong directionality, compact structure and small mutual coupling influence among the antennas.

In addition, the antenna has high gain, can work in a couplant environment with high dielectric constant, and is used for detecting cerebral apoplexy. The antenna has extremely high application value in the field of medical imaging.

2. The radiation field of the planar monopole antenna is TM wave, so that the solution process of the scattered field is simplified, and more accurate dielectric constant values of all brain areas can be obtained.

3. The planar monopole antenna is quite mature in processing technology based on the dielectric substrate, simple in manufacturing process, low in cost and high in yield, and can meet the requirements of low-cost cerebral apoplexy scanner equipment.

Drawings

Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the invention. Also, like reference numerals are used to refer to like parts throughout the drawings. In the drawings:

fig. 1 is a schematic top view and a schematic bottom view of a planar monopole antenna of the present invention.

Fig. 2 is a schematic top view and a schematic bottom view of a non-comb planar monopole antenna.

FIG. 3 is the S of the planar monopole antenna of the present invention₁₁And (4) a simulation result curve graph of the parameters.

FIG. 4 is a S of a non-comb planar monopole antenna₁₁And (4) a simulation result curve graph of the parameters.

Fig. 5-7 are electric field distribution diagrams of the far field region of the planar monopole antenna of the present invention at three operating frequencies of 500MHz, 700MHz and 1GHz, respectively.

Fig. 8-9 are three-dimensional patterns of the planar monopole antenna of the present invention at 0.6GHz frequency and 0.9GHz frequency, respectively.

Description of the reference numerals

100 is a dielectric substrate, 200 is a monopole radiator, 201 is a slot line, 300 is a microstrip feeder, 400 is a metal pad, 401 is a metal cylinder, and 500 is a metal floor.

Detailed Description

Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. It should be understood that the description is illustrative only and is not intended to limit the scope of the present disclosure. Moreover, in the following description, descriptions of well-known structures and techniques are omitted so as to not unnecessarily obscure the concepts of the present disclosure.

Various structural schematics according to embodiments of the present disclosure are shown in the figures. The figures are not drawn to scale, wherein certain details are exaggerated and possibly omitted for clarity of presentation. The shapes of various regions, layers, and relative sizes and positional relationships therebetween shown in the drawings are merely exemplary, and deviations may occur in practice due to manufacturing tolerances or technical limitations, and a person skilled in the art may additionally design regions/layers having different shapes, sizes, relative positions, as actually required.

In the context of the present disclosure, when a layer/element is referred to as being "on" another layer/element, it can be directly on the other layer/element or intervening layers/elements may be present. In addition, if a layer/element is "on" another layer/element in one orientation, then that layer/element may be "under" the other layer/element when the orientation is reversed.

The planar monopole antenna of the present invention is further described with reference to the accompanying drawings.

Fig. 1 is a schematic top view and a schematic bottom view of a planar monopole antenna of the present invention. Specifically, as shown in fig. 1, the planar monopole antenna of the present invention includes: the monopole radiator 200, the upper portion of monopole radiator 200 is provided with many slot lines 201.

The monopole radiator 200 may be aluminum, iron, tin, copper, silver, gold, or platinum metal, or an alloy of any of aluminum, iron, tin, copper, silver, gold, and platinum.

The monopole radiator 200 may be rectangular, square, or elliptical. In one embodiment, the monopole radiator 200 is rectangular and may have a length of 40 to 60mm and a width of 10 to 25 mm; preferably, the length may be 45-50mm and the width may be 15-20 mm. In a specific embodiment, the monopole radiator 200 has a length of 47.0mm and a width of 16.8 mm. By adopting the size parameter, the monopole antenna can work in a frequency band of 500MHz-1GHz required by stroke detection.

In one embodiment, the lower portion of the monopole radiator 200 is provided with two symmetrical chamfers (not shown in fig. 1), and the chamfers can be triangular, and the size of the angle and the side length can be flexibly adjusted according to the requirement of impedance bandwidth. Two symmetrically distributed cut angles may improve the impedance matching of the antenna.

The number and size of the slot lines 201 can be flexibly adjusted according to the operating bandwidth requirements of the antenna. The pitch between two adjacent slot lines 201 is preferably the same. The plurality of slot lines 201 form a comb structure. The monopole radiator 200 is designed as a comb structure, which can achieve broadband impedance matching.

The planar monopole antenna adopts the monopole radiator, so that the planar monopole antenna has a wide frequency band, ensures simple structure and small volume, and can improve the portability of the stroke detection equipment. In addition, the antenna has strong directionality, compact structure and small mutual coupling influence among the antennas. In addition, the antenna has high gain, can work in a couplant environment with high dielectric constant, and is used for detecting cerebral apoplexy. The antenna has extremely high application value in the field of medical imaging.

In one particular embodiment, the planar monopole antenna of the present invention comprises:

a dielectric substrate 100;

a monopole radiator 200, wherein a slot line 201 is arranged at the upper part of the monopole radiator 200, and the monopole radiator 200 is arranged on the upper surface of the dielectric substrate 100;

a microstrip feed line 300 disposed on the upper surface of the dielectric substrate 100 and connected to the lower edge of the monopole radiator 200;

two metal pads 400, wherein the two metal pads 400 are both provided with a metal cylinder 401, and the two metal pads 400 are both arranged on the upper surface of the dielectric substrate 100 and symmetrically arranged on the two sides of the lower part of the microstrip feeder line 300; and

and the metal floor 500 is arranged on the lower surface of the dielectric substrate 100 and below the microstrip feed line 300, and the metal floor 500 is connected with the metal cylinder 401.

The dielectric substrate 100 adopts an epoxy fiberglass cloth substrate FR-4. The dielectric substrate 100 has a dielectric constant of 4.3 to 4.6, a loss tangent value depending on a frequency, and a loss tangent value of about 0.01 at a frequency of 1 GHz. The dielectric substrate 100 has a length and a width greater than those of the monopole radiator 200, respectively. The dielectric substrate 100 has the advantages of mature processing technology, low cost, simple manufacturing process and high yield, and can meet the requirement of low manufacturing cost of the compact comb-shaped planar monopole ultra-wideband antenna applied to stroke detection.

In one embodiment, the dielectric substrate 100 has a rectangular shape, and the monopole radiator 200 has a rectangular shape with cut corners. The long sides of the monopole radiators 200 are arranged in parallel with the long sides of the dielectric substrate 100, and the short sides of the monopole radiators 200 are arranged in parallel with the short sides of the dielectric substrate 100. The center line of the short side of the monopole radiator 200 coincides with the center line of the short side of the dielectric substrate 100.

The microstrip feed line 300 may be aluminum, iron, tin, copper, silver, gold, or platinum metal, or an alloy of any of aluminum, iron, tin, copper, silver, gold, and platinum. In one embodiment, the monopole radiator 200 is rectangular with cut corners and the microstrip feed line 300 is rectangular. The upper edge of the microstrip feed line 300 is connected to the lower edge of the monopole radiator 200, and the lower edge of the microstrip feed line 300 is flush with the lower edge of the dielectric substrate 100. The microstrip feed line 300 is directly connected to the monopole radiator 200 for feeding. The center line of the short side of the microstrip feed line 300 coincides with the center line of the short side of the monopole radiator 200, ensuring structural symmetry.

In one embodiment, the microstrip feed line 300 and the metal pad 400 are connected using an SMA (Sub-Miniature a) connector, wherein the interface inner core of the SMA connector is connected to the microstrip feed line 300 and the interface outer core of the SMA connector is connected to the metal pad 400. The SMA connector is low in price, and the production cost of the planar monopole antenna can be reduced.

The metal pad 400 may be aluminum, iron, tin, copper, silver, gold, or platinum metal, or an alloy of any one of aluminum, iron, tin, copper, silver, gold, and platinum. The lower edge of the metal pad 400 is flush with the lower edge of the dielectric substrate 100. A plurality of metal columns 401, for example 1-10, may be disposed on the metal pad 400. The number of the metal columns 401 in the present invention is not particularly limited as long as the microstrip feed line 300 and the metal ground plane 500 can be electrically connected.

The metal flooring 500 may be aluminum, iron, tin, copper, silver, gold, or platinum metal, or an alloy of any one of aluminum, iron, tin, copper, silver, gold, and platinum. The metal floor 500 may have a rectangular shape. The upper edge of the metal floor 500 is flush with the upper edge of the microstrip feed line 300, the lower edge of the metal floor 500 is flush with the lower edge of the dielectric substrate 100, the left edge of the metal floor 500 is flush with the left edge of the dielectric substrate 100, and the right edge of the metal floor 500 is flush with the right edge of the dielectric substrate 100.

The inventor conducts simulation verification on the comb-shaped planar monopole antenna by means of a finite element electromagnetic simulation algorithm S₁₁The curves of the parameter (input port return loss) simulation results are shown in fig. 3. In addition, the inventor also carried out simulation verification on a non-comb planar monopole antenna (as shown in FIG. 2), S₁₁The curve of the parameter simulation results is shown in fig. 4. Comparing S of the two antennas₁₁Parameters can be seen that the comb-shaped planar monopole antenna provided by the invention has S within the frequency band range of 0.5-1.5GHz₁₁The values are all less than-10 dB; while the non-comb planar monopole antenna is in the S part of the frequency band of 0.5-1.5GHz₁₁The value is greater than-10 dB; this shows that the comb-shaped planar monopole antenna of the present invention greatly broadens the bandwidth.

Fig. 5-7 are electric field distribution diagrams of the far field region of the planar monopole antenna of the present invention at three operating frequencies of 500MHz, 700MHz and 1GHz, respectively. It can be seen that the far-field radiation field of the planar monopole antenna of the present invention is TM wave (Transverse magnetic wave). This simplifies the solution process for the scattered field, which results in more accurate values of the permittivity of various regions of the brain.

Fig. 8-9 are three-dimensional patterns of the planar monopole antenna of the present invention at 0.6GHz frequency and 0.9GHz frequency, respectively. It can be seen that the planar monopole antenna of the invention has strong directionality.

The planar monopole antenna has wider bandwidth and stronger directionality, and can meet the application requirements of medical imaging.

The planar monopole antenna can work in a liquid coupling agent with the relative dielectric constant of 30, the dielectric constant distribution of each area in the brain is obtained by inverting the S parameter of each antenna array element, the internal structure of the brain is reflected, and the local bleeding and ischemia conditions are reflected by solving the rise and fall of the dielectric constant in a lesion area, so that the detection of the stroke is realized.

The planar monopole antenna of the invention can be formed into a ring array. The annular array is fixed on an imaging detection device and can be applied to scenes such as ambulances, physical examination rooms and the like; the annular array can also be fixed to an imaging detection device and made into a small, lightweight wearable device that allows for home use by the patient.

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the appended claims.