CN102810723B - Method for preparing buried medium antenna - Google Patents

Abstract

The invention provides a method for preparing a buried medium antenna, and belongs to the technical field of electromagnetic fields and microwaves. The preparation method comprises the following steps of: totally burying a self-designed copper antenna into a ceramic medium material doped with an yttrium group of rare earth formula to ensure that a metal part of the antenna is not exposed; forming and manufacturing the copper antenna; sintering the copper antenna at a specific temperature; and manually reducing the temperature of the sintered copper antenna to prepare the buried medium antenna of which the metal part of the antenna can be seamlessly integrated with a buried medium. By the ceramic medium, the antenna is subjected to the sintering and is buried into the ceramic medium, so that the antenna can be seamlessly integrated with the ceramic medium to guarantee stable performance; the metal part of the antenna is insusceptible to corrosion and environmental interference on the metal part is reduced; a bismuthic acid barium-based ceramic material is adopted to fill the antenna, and a melting point of the bismuthic acid barium-based ceramic material is lower than that of a copper sheet, so that melting and deformation of the copper sheet in the sintering process are avoided, and the design requirement of the buried medium antenna can be easily met; and therefore, the rate of finished products is improved.

Description

A kind of medium buries the preparation method of antenna

Technical field

The present invention relates to a kind of preparation method, be specifically related to the preparation method that a kind of medium buries antenna, belong to Electromagnetic Field and Microwave Technology field.

Background technology

At present, antenna mainly can be divided into electronically small antenna (as vehicle-mounted amplitude modulation vertical reception antenna), resonant antenna (as dipole antenna), broad-band antenna (as helical antenna) and aperture antenna (as electromagnetic horn) etc., and these antenna is all the surface being exposed to equipment at present, can not be conformal with equipment when these antenna or installation, a definite limitation is subject to during large-scale production, be exactly that production cost is higher, or the antenna metal part be exposed in air is subject to oxide etch etc.

Medium buries antenna, as the term suggests exactly antenna is buried the class antenna in medium.According to design feature, antenna is buried to medium and made following regulation: medium buries antenna and refers to and all buried in medium by antenna, and there is certain distance between any edge that any edge of each component units of regulation antenna all should be corresponding with burying dielectric substrate, namely the edge of each component units of antenna all must be less than the distance of substrate edge corresponding thereto to center of antenna (to ensure from substrate side to the distance of center of antenna, the each component units edge of antenna is not exposed at outside medium), only in this way just can be referred to as medium and bury microstrip antenna.It should be emphasized that, here it is be different from the dielectric overlay antenna that current Chinese scholars are studying that the medium specified buries microstrip antenna, because the latter only by dielectric overlay on the component units of antenna, this covering simultaneously allows have gap to exist between medium and antenna element, and allow antenna element edge to even up mutually with substrate edge, namely allow the side open of antenna element; In addition, also have a kind of by a part for antenna insertion medium, although also there is foreign scholar to make medium bury antenna, although do not meet the implication of afore mentioned rules, so be not that the said medium of the present invention buries antenna.

Although begun one's study, medium buries antenna, but also antenna not to be imbedded in completely in medium and to process the Theory and technology of all-in-one-piece comparative maturity with medium, especially a kind of complete feasible preparation method is not also had, because antenna and medium are processed into integrated technique difficulty is large and yield rate is low, and antenna is generally copper sheet, its fusing point is lower, in the selection of medium when not affecting antenna performance, ensure again to cause copper sheet to melt distortion in sintering process, therefore difficulty is large.

Summary of the invention

In view of this, the invention provides the preparation method that a kind of medium buries antenna, by copper entire physical all being buried in the ceramic medium material of doped with yttrium group rare-earth formula, then carry out shaping and sinter at a certain temperature, manual control temperature progressively cools rear medium that is obtained and the seamless combination of medium and buries antenna.

Medium buries a preparation method for antenna, and its preparation methods steps is as follows:

Step one: try to achieve the wavelength of electromagnetic wave at dielectric space according to formula (1-1);

${\mathrm{\λ}}_{\mathrm{\ϵ}}=\frac{{\mathrm{\λ}}_0}{\sqrt{{\mathrm{\ϵ}}_r}}---(1-1)$

Wherein, λ ₀for electromagnetic wave wavelength in free space, λ _εfor the wavelength of electromagnetic wave in dielectric space, ε _rfor dielectric constant;

Step 2: the wavelength X of trying to achieve according to step one _ε, then calculate the distance d in dielectric space between each antenna element according to formula (2-1) ~ (2-2) _εwith the length l of each antenna element _n;

d _ε＝k ₁λ _ε； （2-1）

l _n＝K _nk ₂λ _ε； （2-2）

Wherein, k ₁, k ₂, K _nbe coefficient, k ₁span be [0.2,2.5], k ₂span be [0.3,0.49], K _n=1-e ^-(n-1), the integer during n gets [1, m], m is the antenna element number in antenna;

Step 3: choose l ₁1/10th as the width of antenna element, thus determine the size of current antenna;

Step 4: the size according to current antenna carries out emulation experiment, and observes transfer function curve, to judge whether the design size of current antenna is best;

Step 5: if the size that step 3 obtains is not best, then repeats step 2 ~ step 4, namely adjust k ₁, k ₂, K _nuntil obtain the size of optimal antenna;

Step 6: the optimum size obtaining antenna according to step 5 makes antenna element formation bar shaped copper sheet, and is fixed on transparent plastic sheet with 505 Instant cements by each antenna element;

Step 7: choose yttrium group rare-earth and mix with mass ratio 1/1000 ~ 5/1000 with bismuthic acid barium-based ceramic material, is formed and buries doped dielectric material;

Step 8: the center plastic plate with bar shaped copper sheet obtained in step 6 being placed on mould, and carry out filling until bar shaped copper sheet is buried completely with the doped dielectric material that step 6 is obtained;

Step 9: the mould after filling in step 8 is shaken, makes Filled Dielectrics even and compressing, send in sintering furnace after removing mould;

Step 10: control sintering furnace temperature between 850-880 DEG C, after sintering 3-4h, progressively cooling obtains medium and buries antenna.

If Yagi spark gap chip aerial selected by the antenna buried, then before step 3, need the quantity of determining to guide into a period of time.

Beneficial effect: (1) the present invention by adopt ceramic dielectric through oversintering antenna buried with wherein, antenna and ceramic dielectric seamlessly can be organically combined, make medium bury antenna performance more stable; (2) the present invention buries antenna by adopting medium, antenna metal part is not easily corroded and can also reduces the interference of environment to it; (3) the present invention adopts bismuthic acid barium-based ceramic material to fill, and because the fusing point of bismuthic acid barium-based ceramic material is lower than the fusing point of copper sheet, copper sheet in sintering process can not be caused to melt distortion, can be easier to reach the designing requirement that medium buries antenna, improve yield rate; (4) because the dielectric constant of ceramic dielectric is greater than 4, the electromagnetic wavelength in medium is made to shorten effect obvious, and antenna size and the proportional relation of wavelength, namely the present invention buries by ceramic dielectric the volume that antenna can reduce antenna.

Accompanying drawing explanation

Fig. 1 is the flow chart of preparation method of the present invention

Fig. 2 is the structure chart of Yagi spark gap chip aerial of the present invention.

Detailed description of the invention

To develop simultaneously embodiment below in conjunction with accompanying drawing, describe the present invention.

As shown in Figure 1, the invention provides the preparation method that a kind of medium buries antenna, its preparation methods steps is as follows:

Step one: try to achieve the wavelength of electromagnetic wave at dielectric space according to formula (1-1);

${\mathrm{\λ}}_{\mathrm{\ϵ}}=\frac{{\mathrm{\λ}}_0}{\sqrt{{\mathrm{\ϵ}}_r}}---(1-1)$

Wherein, λ ₀for electromagnetic wave wavelength in free space (free space refers to that medium is air), λ _εfor the wavelength of electromagnetic wave in dielectric space, ε _rfor dielectric constant;

Step 2: antenna is generally made up of several antenna elements, has certain distance between each antenna element; According to the wavelength X that step one is tried to achieve _ε, then calculate the distance d in dielectric space between each antenna element according to formula (2-1) ~ (2-2) _εwith the length l of each antenna element _n;

d _ε＝k ₁λ _ε； （2-1）

l _n＝K _nk ₂λ _ε； （2-2）

Wherein, k ₁, k ₂, K _nbe coefficient, k ₁span be [0.2,2.5], k ₂span be [0.3,0.49], K _n=1-e ^-(n-1), the integer during n gets [1, m], m is the antenna element number in antenna.In general m can not more than 11.

For Yagi spark gap chip aerial, as shown in Figure 2, it comprises reflection oscillator, excitation oscillator, director dipole, and each oscillator just refers to each antenna element.Wherein director dipole can be multiple, and its quantity is determined according to the required value (namely needing electromagnetic intensity) of antenna gain.

Fig. 2 shows the situation of two director dipoles, then m=4, the length l of reflection oscillator _r=l ₁, the length 2l of excitation oscillator _s=l ₂, the length of the first director dipole is l ₃, the length of the second director dipole is l ₄, all utilize formula (2-2) to calculate.

Step 3: choose l ₁1/10th as the width of antenna element, thus determine the size of current antenna.

Step 4: the size according to current antenna carries out emulation experiment, and observe transfer function curve (it is electromagnetic intensity curve for antenna exports), to judge whether the design size of current antenna is best.

This is judged as this area routine techniques means, and it judges by the waveform of transfer function curve the standard whether antenna performance reaches required, if so, then thinks that current antenna is of a size of the best.

Step 5: if the size that step 4 obtains is not best (by exporting electromagnetic intensity curve to judge), then repeats step 2 ~ step 4, namely adjust k ₁, k ₂, K _nuntil obtain the optimum size of antenna.

Step 6: the optimum size obtaining antenna according to step 5 makes antenna element formation bar shaped copper sheet, and is fixed on transparent plastic sheet by each antenna element with 505 Instant cements.

Step 7: choose yttrium group rare-earth and mix with mass ratio 1/1000 ~ 5/1000 with bismuthic acid barium-based ceramic material, is formed and buries doped dielectric material.

Because the fusing point of bismuthic acid barium-based ceramic material is lower than the fusing point of copper sheet, copper sheet in sintering process can not be caused to melt distortion, can be easier to reach the designing requirement that medium buries antenna, improve yield rate, and increase yttrium group rare-earth can improve the magnetic of antenna and the hardness of medium.

Step 8: the center plastic plate with bar shaped copper sheet obtained in step 6 being placed on mould, and carry out filling until bar shaped copper sheet is buried completely with the doped dielectric material that step 7 is obtained, and be full of mould;

Step 9: shaken by the mould after filling in step 8, makes Filled Dielectrics even and compressing (can be square, cuboid, cylinder and spheroid), sends in sintering furnace after removing mould;

Step 10: control sintering furnace temperature between 850-880 DEG C, after sintering 3-4h, manual control temperature progressively cools and obtains medium and bury antenna.

Embodiment one: the mass ratio choosing yttrium group rare-earth and bismuthic acid barium-based ceramic material is 1/1000, controls the temperature of sintering furnace and is 850 DEG C and after sintering 3h, and manual control temperature progressively cools and obtains medium and bury antenna.

Embodiment two: the mass ratio choosing yttrium group rare-earth and bismuthic acid barium-based ceramic material is 3/1000, controls the temperature of sintering furnace and is 860 DEG C and after sintering 3.5h, and manual control temperature progressively cools and obtains medium and bury antenna.

Embodiment three: the mass ratio choosing yttrium group rare-earth and bismuthic acid barium-based ceramic material is 5/1000, controls the temperature of sintering furnace and is 880 DEG C and after sintering 4h, and manual control temperature progressively cools and obtains medium and bury antenna.

The obtained medium of above-described embodiment one ~ embodiment three buries antenna, its antenna with bury that medium is seamless to be organically combined into one, its volume is little and functional.

In sum, these are only preferred embodiment of the present invention, be not intended to limit protection scope of the present invention.Within the spirit and principles in the present invention all, any amendment done, equivalent replacement, improvement etc., all should be included within protection scope of the present invention.

Claims (2)

1. medium buries a preparation method for antenna, it is characterized in that, its preparation methods steps is as follows:

Step one: according to formula try to achieve the wavelength of electromagnetic wave at dielectric space;

Wherein, λ ₀for electromagnetic wave wavelength in free space, λ _εfor the wavelength of electromagnetic wave in dielectric space, ε _rfor dielectric constant;

Step 2: the wavelength X of trying to achieve according to step one _ε, then according to formula d _ε=k ₁λ _εand l _n=K _nk ₂λ _εcalculate the distance d in dielectric space between each antenna element _εwith the length l of each antenna element _n;

Wherein, k ₁, k ₂, K _nbe coefficient, k ₁span be [0.2,2.5], k ₂span be [0.3,0.49], K _n=1-e ^-(n-1), the integer during n gets [1, m], m is the antenna element number in antenna;

Step 3: choose l ₁1/10th as the width of antenna element, thus determine the size of current antenna;

Step 4: the size according to current antenna carries out emulation experiment, and observes transfer function curve, to judge whether the design size of current antenna is best;

Step 5: if the size that step 3 obtains is not best, then repeats step 2 ~ step 4, namely adjust k ₁, k ₂, K _nuntil obtain the size of optimal antenna;

Step 6: the optimum size obtaining antenna according to step 5 makes antenna element formation bar shaped copper sheet, and is fixed on transparent plastic sheet with 505 Instant cements by each antenna element;

Step 7: choose yttrium group rare-earth and mix with mass ratio 1/1000 ~ 5/1000 with bismuthic acid barium-based ceramic material, is formed and buries doped dielectric material;

Step 8: the center plastic plate with bar shaped copper sheet obtained in step 6 being placed on mould, and carry out filling until bar shaped copper sheet is buried completely with the doped dielectric material that step 6 is obtained;

Step 9: the mould after filling in step 8 is shaken, makes Filled Dielectrics even and compressing, send in sintering furnace after removing mould;

Step 10: control sintering furnace temperature between 850-880 DEG C, after sintering 3-4h, manual control temperature progressively cools and obtains medium and bury antenna.

2. a kind of medium as claimed in claim 1 buries the preparation method of antenna, it is characterized in that, if Yagi spark gap chip aerial selected by the antenna buried, then before step 3, needs the quantity of determining to guide into a period of time.