CN114843759B

CN114843759B - Monopole water antenna

Info

Publication number: CN114843759B
Application number: CN202210282695.1A
Authority: CN
Inventors: 华昌洲; 张宇新; 黄雪琴; 陈益; 姜菲; 刘锦剑; 王健
Original assignee: Ningbo University
Current assignee: Ningbo University
Priority date: 2022-03-22
Filing date: 2022-03-22
Publication date: 2023-04-14
Anticipated expiration: 2042-03-22
Also published as: CN114843759A

Abstract

The invention discloses a monopole water antenna, which comprises a coaxial cable, a metal base plate, a Teflon base, a first water tank, a second water tank and four arc-shaped water arms, wherein the Teflon base is positioned above the metal base plate, the lower end surface of the Teflon base is attached to the upper end surface of the metal base plate, the first water tank is realized by arranging a cylindrical cavity on a cylinder main body, the cylinder main body is positioned above the Teflon base, the lower end surface of the cylinder main body is attached to the upper end surface of the Teflon base, an inner core of the coaxial cable sequentially penetrates through the metal base plate, the Teflon base and the bottom of the cylinder main body and then enters the cylindrical cavity, the second water tank is realized by arranging a truncated cone cavity on the truncated cone main body, the small head end of the truncated cone main body is attached to the upper end surface of the cylindrical main body, four through holes communicated with the truncated cone cavity are uniformly arranged on the side wall of the truncated cone main body at intervals along a circle, and the four arc-shaped water arms are correspondingly arranged at four through holes one to one; the omnidirectional radiation antenna has the advantages of simple structure and capability of realizing omnidirectional radiation in two working frequency bands.

Description

Monopole water antenna

Technical Field

The invention relates to a water antenna, in particular to a monopole water antenna.

Background

Water is one of indispensable substances in our lives and plays an important role in daily life. The water has the characteristics of easy acquisition, transparency, fluidity and the like. Compared with the traditional antenna, the water antenna designed based on the water characteristic not only has low cost and convenient access, but also has the characteristics of concealment and emergency response, and is popular in recent years.

The existing monopole water antenna is loaded with water with two different conductivities, namely seawater and purified water, and the seawater and the purified water respectively realize one-frequency-band work, so that dual-frequency-band work is never realized, wherein the first working frequency band realized by the seawater is a wifi frequency band (2.420-2.4835 GHz) and is used for indoor communication, and the second working frequency band realized by the purified water is an emergency communication frequency band (1.544-1.646 GHz) and is used for communication in case of emergency. However, because the existing monopole water antenna needs to load seawater and pure water at the same time, it needs to design the radiation structures of seawater and pure water respectively, so that the structure is relatively complex, and meanwhile, the water columns formed in the radiation structures of seawater and pure water are all cylinders, so that the radiation directions in two frequency bands are not omnidirectional radiation.

Disclosure of Invention

The technical problem to be solved by the invention is to provide a monopole water antenna which is simple in structure and can realize omnidirectional radiation in two working frequency bands.

The technical scheme adopted by the invention for solving the technical problems is as follows: a monopole water antenna comprises a coaxial cable, a metal base plate, a Teflon base, a first water tank, a second water tank and four identical arc water arms, wherein the arc water arms are realized by arc water pipes with openings at the upper ends and closed lower ends, the metal base plate is a circular plate, the Teflon base is cylindrical, the Teflon base is positioned above the metal base plate and is coaxial with the metal base plate, the lower end surface of the Teflon base is attached to the upper end surface of the metal base plate, the radius of the Teflon base is smaller than that of the metal base plate, the first water tank is realized by arranging a cylindrical cavity on the cylinder body, the cylindrical cavity is coaxial with the cylinder body, the upper end surface of the cylindrical cavity is flush with the upper end surface of the cylinder body, and the height of the cylindrical cavity is equal to that of the cylinder body, the radius of the cylindrical cavity is 4mm smaller than that of the cylindrical main body, the cylindrical main body is positioned above the Teflon base, the cylindrical main body and the Teflon base are coaxial, the lower end face of the cylindrical main body is attached to the upper end face of the Teflon base, the lower end face of the cylindrical main body is sealed by the Teflon base, the radius of the cylindrical main body is smaller than that of the Teflon base, an inner core of a coaxial cable sequentially penetrates through the metal bottom plate, the Teflon base and the bottom of the cylindrical main body and then enters the cylindrical cavity, the second water tank is realized by arranging a cone table cavity on the cone table main body, the cone table main body is provided with a large head end and a small head end, and the radius of the small head end of the cone table main body is equal to that of the cylindrical main body, the small head end of the truncated cone main body is positioned below the large head end of the truncated cone main body, the truncated cone main body is coaxial with the cylindrical main body, the small head end of the truncated cone main body is attached to the upper end face of the cylindrical main body, the truncated cone cavity is coaxial with the truncated cone main body, the truncated cone cavity is provided with a large head end and a small head end, the small head end of the truncated cone cavity is flush with the small head end of the truncated cone main body, the large head end of the truncated cone cavity is flush with the large head end of the truncated cone main body, the truncated cone cavity is coaxial with the truncated cone main body, the radius of the small head end of the truncated cone cavity is equal to the radius of the cylindrical cavity, four through holes communicated with the truncated cone cavity are uniformly arranged on the side wall of the truncated cone main body along a circle at intervals, four arc-shaped water arms are correspondingly arranged at four through holes one by one, and are communicated with the truncated cone cavity; the thickness of the side wall of the arc-shaped water arm is 2mm, and the thickness of the closed part at the lower end of the arc-shaped water arm is 1mm; recording an included angle between the arc-shaped water arm and the metal bottom plate as alpha, wherein the value range of the alpha is 45-60 degrees; the height of the Teflon base is recorded as H1, the range of H1 is 1-4mm, the height of the inner core of the coaxial cable entering the cylindrical cavity is recorded as H2, the range of H2 is 8-12mm, the height of the cylindrical cavity is recorded as H3, the range of H3 is 45-65mm, the distance from the center of the through hole to the plane of the lower end face of the metal bottom plate is recorded as H4, the range of H4 is 55-65mm, the height of the cone table main body is recorded as H5, the range of H5 is 15-25mm, the radius of the metal bottom plate is recorded as R1, the range of R1 is 20-60mm, the inner diameter of the arc water arm is recorded as R2, the range of R2 is 1-1.5mm, the outer diameter of the arc water arm is recorded as R3, the range of R3 is 3-3.5mm, the diameter of the cone table head is recorded as the range of D1, the range of D1 is 6-8mm, the outer diameter of the cone table head is recorded as the diameter of the cone table head is 16-10 mm, and the diameter of the cone head is recorded as the large head.

The material of the metal bottom plate is copper, the materials of the cylindrical main body, the conical frustum main body and the four arc-shaped water arms are all dielectric constant of 2.75, the loss is 0.023D printing material washed xc11122, the diameter of the coaxial cable inner core with alpha =56.5 degrees is 1.27mm, H1=1mm, H2=10mm, H3=50mm, H4=61.5mm, H5= 2mm, R1=30mm, R2=1mm, R3=3mm, D1=6mm, D2=14mm, D3=14mm, D4=28mm.

Compared with the prior art, the monopole water antenna has the advantages that the monopole water antenna is formed by the coaxial cable, the metal bottom plate, the Teflon base, the first water tank, the second water tank and the four identical arc-shaped water arms, the arc-shaped water arms are realized by adopting the arc-shaped water pipes, the first water tank is realized by arranging the cylindrical cavity on the cylindrical main body, the second water tank is realized by arranging the truncated cone cavity on the truncated cone main body, when the monopole water antenna works, purified water is filled in the first water tank, the second water tank and the four arc-shaped water arms, external excitation electromagnetic waves are connected into the coaxial cable, most of the excitation electromagnetic waves are gathered at the bottom of the first water tank through the Telfon base and then are transmitted outwards through the first water tank, the second water tank and the four arc-shaped water arms in sequence, and in the transmission process of the electromagnetic waves, because the sizes of the first water tank and the second water tank are changed, the electromagnetic wave transmission device has the advantages that the transmission boundary of the electromagnetic wave in pure water is changed, two working frequency bands including a wifi frequency band and an emergency communication frequency band are generated, the electromagnetic wave can enter the arc-shaped water arms to radiate outwards after passing through the first water tank and the second water tank under the matching of the four arc-shaped water arms, so that the radiation directions in the two working frequency bands can be compensated, the two working frequency bands can realize omnidirectional radiation, the size of the four arc-shaped water arms is smaller than that of the first water tank and that of the second water tank, only a small part of the electromagnetic wave can radiate outwards through the four arc-shaped water arms, the influence on the two working frequency bands is reduced, and the normal work of the two working frequency bands is ensured.

Drawings

Fig. 1 is a perspective view of a monopole water antenna of the present invention;

fig. 2 is an exploded view of the monopole water antenna of the present invention;

fig. 3 is a cross-sectional view of a monopole water antenna of the present invention;

FIG. 4 is a return loss diagram of the monopole water antenna of the present invention at two resonance points of 1.68GHz and 2.51 GHz;

FIG. 5 is a two-dimensional gain pattern for a monopole water antenna of the present invention at a 1.68GHz resonance point;

fig. 6 is a two-dimensional gain pattern of the monopole water antenna of the present invention at the 2.51GHz resonance point.

Detailed Description

The invention is described in further detail below with reference to the following examples of the drawings.

Example (b): as shown in fig. 1-3, a monopole water antenna comprises a coaxial cable 1, a metal base plate 2, a Teflon base 3, a first water tank 4, a second water tank 5 and four identical arc-shaped water arms 6, wherein the arc-shaped water arms 6 are realized by arc-shaped water pipes with openings at the upper ends and closed lower ends, the metal base plate 2 is a circular plate, the Teflon base 3 is cylindrical, the Teflon base 3 is positioned above the metal base plate 2, the Teflon base 3 is coaxial with the metal base plate 2, the lower end surface of the Teflon base 3 is attached to the upper end surface of the metal base plate 2, the radius of the Teflon base 3 is smaller than that of the metal base plate 2, the first water tank 4 is realized by arranging a cylindrical cavity 42 on a cylinder body 41, the cylindrical cavity 42 is coaxial with the cylinder body 41, the upper end surface of the cylindrical cavity 42 is flush with the upper end surface of the cylinder body 41, the height of the cylindrical cavity 42 is equal to that of the cylinder body 41, the radius of the cylindrical cavity 42 is 4mm smaller than that of the cylindrical body 41, the cylindrical body 41 is positioned above the Teflon base 3, the cylindrical body 41 and the Teflon base 3 are coaxial, the lower end face of the cylindrical body 41 is attached to the upper end face of the Teflon base 3, the lower end face of the cylindrical body 41 is sealed by the Teflon base 3, the radius of the cylindrical body 41 is smaller than that of the Teflon base 3, an inner core of the coaxial cable 1 sequentially penetrates through the metal base plate 2, the Teflon base 3 and the bottom of the cylindrical body 41 and then enters the cylindrical cavity 42, the second water tank 5 is realized by arranging a cone frustum cavity 52 on the cone frustum body 51, the cone frustum body 51 is provided with a large end and a small end, the radius of the small end of the cone frustum body 51 is equal to that of the cylindrical body, the small end of the cone frustum body 51 is positioned below the large end of the small end, and the cone frustum body 51 is coaxial with the cylindrical body, the small end of the circular truncated cone main body 51 is attached to the upper end face of the cylindrical main body, the circular truncated cone cavity 52 is coaxial with the circular truncated cone main body 51, the circular truncated cone cavity 52 is provided with a large end and a small end, the small end of the circular truncated cone cavity 52 is flush with the small end of the circular truncated cone main body 51, the large end of the circular truncated cone cavity 52 is flush with the large end of the circular truncated cone main body 51, the circular truncated cone cavity 52 is coaxial with the circular truncated cone main body 51, the radius of the small end of the circular truncated cone cavity 52 is equal to that of the cylindrical cavity 42, four through holes communicated with the circular truncated cone cavity 52 are uniformly arranged on the side wall of the circular truncated cone main body 51 at intervals along a circle, the four arc-shaped water arms 6 are correspondingly installed at four through holes one by one, and the four arc-shaped water arms 6 are communicated with the circular truncated cone cavity 52; the thickness of the side wall of the arc-shaped water arm 6 is 2mm; the thickness of the sealing position of the lower end of the arc-shaped water arm 6 is 1mm; recording an included angle between the arc-shaped water arm 6 and the metal bottom plate 2 as alpha, wherein the value range of the alpha is 45-60 degrees; the height of the Teflon base 3 is recorded as H1, the value range of H1 is 1-4mm, the height of the inner core of the coaxial cable 1 entering the cylindrical cavity 42 is recorded as H2, the value range of H2 is 8-12mm, the height of the cylindrical cavity 42 is recorded as H3, the value range of H3 is 45-65mm, the distance from the center of the through hole to the plane of the lower end face of the metal bottom plate 2 is recorded as H4, the value range of H4 is 55-65mm, the height of the cone frustum main body 51 is recorded as H5, the value range of H5 is 15-25mm, the radius of the metal bottom plate 2 is recorded as R1, the numerical range of R1 is 20-60mm, the inner diameter of the arc-shaped water arm 6 is recorded as R2, the numerical range of R2 is 1-1.5mm, the outer diameter of the arc-shaped water arm 6 is recorded as R3, the numerical range of R3 is 3-3.5mm, the diameter of the cylindrical cavity 42 is recorded as D1, the numerical range of D1 is 6-8mm, the diameter of the cylindrical main body is recorded as D2, the numerical range of D2 is 14-16mm, the diameter of the large head end of the cone frustum cavity 52 is recorded as D3, the numerical range of D3 is 10-16mm, the diameter of the large head end of the cone frustum main body 51 is recorded as D4, and the numerical range of D4 is 20-30mm.

In this embodiment, the material of the metal base plate 2 is copper, the materials of the cylindrical body, the truncated cone body 51 and the four arc-shaped water arms 6 are all the materials having a dielectric constant of 2.75, the losses are all 0.023D printing material watermill xc11122, the diameter of the inner core of the α =56.5 ° coaxial cable 1 is 1.27mm, H1=1mm, H2=10mm, H3=50mm, H4=61.5mm, H5= 2mm, R1=30mm, R2=1mm, R3=3mm, D1=6mm, D2=14mm, D3=14mm, and D4=28mm. The emergency communication device has the advantages of meeting the requirements of emergency communication frequency bands and wifi frequency bands, having the requirement of omnidirectional radiation, and being small in size.

The return loss diagrams of the monopole water antenna in the wifi frequency band and the emergency communication frequency band are shown in fig. 4, and the analysis of fig. 4 shows that: the invention has-10 dB working bandwidth of 1.53GHz-1.94GHz when the maximum return loss frequency is 1.68GHz and 2.51GHz respectively corresponding to the two working frequency bands, absolute bandwidth of 410MHz, -10dB working bandwidth of 2.34GHz-2.60GHz when the absolute bandwidth is 2.51GHz, absolute bandwidth of 260MHz, maximum gain of 1.6dBi and 2.3dBi respectively corresponding to the maximum return loss frequency, and depth of-24.9 dB and-19.6 dB respectively corresponding to the maximum return loss frequency. Therefore, the invention can well meet the working requirements of two working frequency bands.

The two-dimensional gain directional pattern of the monopole water antenna of the invention under the frequency of 1.68GHz is shown in figure 5, and the two-dimensional gain directional pattern of the monopole water antenna of the invention under the frequency point of 2.51GHz is shown in figure 6, wherein E _ Plane is a yoz surface in a 3D coordinate, and H _ Plane is an xoy surface in the 3D coordinate. As can be seen from the analysis of fig. 5 and 6: the maximum return loss frequencies respectively corresponding to the two working frequency bands are respectively 1.68Hz and 2.51Hz, and the maximum gain values are respectively 1.6dBi and 2.3dBi. Therefore, the invention has higher gain on the basis of realizing omnidirectional radiation.

Claims

1. A monopole water antenna is characterized by comprising a coaxial cable, a metal bottom plate, a Teflon base, a first water tank, a second water tank and four identical arc-shaped water arms, wherein the arc-shaped water arms are realized by arc-shaped water pipes with openings at the upper ends and closed lower ends, the metal bottom plate is a circular plate, the Teflon base is cylindrical and is positioned above the metal bottom plate, the Teflon base is coaxial with the metal bottom plate, the lower end surface of the Teflon base is attached to the upper end surface of the metal bottom plate, the radius of the Teflon base is smaller than that of the metal bottom plate, the first water tank is realized by arranging a cylindrical cavity on the cylinder body, the cylindrical cavity is coaxial with the cylinder body, the upper end surface of the cylindrical cavity is flush with the upper end surface of the cylinder body, the height of the cylindrical cavity is equal to that of the cylindrical body, the radius of the cylindrical cavity is 4mm smaller than that of the cylindrical body, the cylindrical body is positioned above the Teflon base, the cylindrical body and the Teflon base are coaxial, the lower end face of the cylindrical body is attached to the upper end face of the Teflon base, the lower end face of the cylindrical body is sealed by the Teflon base, the radius of the cylindrical body is smaller than that of the Teflon base, an inner core of a coaxial cable sequentially penetrates through the metal bottom plate, the Teflon base and the bottom of the cylindrical body and then enters the cylindrical cavity, the second water tank is realized by arranging a circular truncated cone cavity on the circular truncated cone body, and the circular truncated cone body is provided with a large head end and a small head end, the radius of the small head end of the truncated cone main body is equal to that of the cylindrical main body, the small head end of the truncated cone main body is positioned below the large head end of the truncated cone main body, the truncated cone main body is coaxial with the cylindrical main body, the small head end of the truncated cone main body is attached to the upper end face of the cylindrical main body, the truncated cone cavity is coaxial with the truncated cone main body, the truncated cone cavity is provided with a large head end and a small head end, the small head end of the truncated cone cavity is flush with the small head end of the truncated cone main body, the large head end of the truncated cone cavity is flush with the large head end of the truncated cone main body, the truncated cone cavity is coaxial with the truncated cone main body, the radius of the small head end of the truncated cone cavity is equal to that of the cylindrical cavity, four through holes communicated with the truncated cone cavity are uniformly arranged on the side wall of the truncated cone main body at intervals along a circle, the four arc-shaped water arms are correspondingly arranged at four through holes one by one, and are communicated with the truncated cone cavity; the thickness of the side wall of the arc-shaped water arm is 2mm, and the thickness of the closed part at the lower end of the arc-shaped water arm is 1mm;

recording an included angle between the arc-shaped water arm and the metal bottom plate as alpha, wherein the value range of the alpha is 45-60 degrees; the height of the Teflon base is recorded as H1, the range of H1 is 1-4mm, the height of the inner core of the coaxial cable entering the cylindrical cavity is recorded as H2, the range of H2 is 8-12mm, the height of the cylindrical cavity is recorded as H3, the range of H3 is 45-65mm, the distance from the center of the through hole to the lower end face of the metal bottom plate is recorded as H4, the range of H4 is 55-65mm, the height of the cone table main body is recorded as H5, the range of H5 is 15-25mm, the radius of the metal bottom plate is recorded as R1, the range of R1 is 20-60mm, the inner diameter of the arc water arm is recorded as R2, the range of R2 is 1-1.5mm, the outer diameter of the arc water arm is recorded as R3, the range of R3 is 3-3.5mm, the diameter of the cylindrical cavity is recorded as D1, the range of D1 is 6-8mm, the outer diameter of the arc water arm is recorded as R3, the range of the diameter of the cylindrical cavity is recorded as D2, the range of the diameter of the head is recorded as D4-16 mm, and the range of the diameter of the head of the cone table head is recorded as R1-16 mm.

2. A monopole water antenna according to claim 1, wherein the material of the metal base plate is copper, the material of the cylindrical main body, the material of the conical frustum main body and the material of the four arc-shaped water arms are all dielectric constant 2.75, printed material WATERSHARED xc11122 with loss 0.023D, the diameter of the coaxial cable core with α =56.5 ° is 1.27mm, H1=1mm, H2=10mm, H3=50mm, H4=61.5mm, H5=20mm, R1=30mm, R2=1mm, R3=3mm, D1=6mm, D2=14mm, D3=14mm, D4=28mm.