CN104134834A - Waveguide mode exciting device - Google Patents

Abstract

The invention provides a waveguide mode exciting device which comprises a first mode conversion assembly and a second mode conversion assembly. The first mode conversion assembly is used for converting the mode of millimeter waves from a TE 10 fundamental mode to a circular waveguide TE61 mode, and the second mode conversion assembly is used for being communicated with the first mode conversion assembly and converting the mode of the millimeter waves from the circular waveguide TE61 mode to the circular waveguide TE62 mode. According to the waveguide mode exciting device, by means of a mode conversion chain of converting the rectangular waveguide TE10 mode into the circular waveguide TE62 mode, the high-purity target mode output is obtained, a parasitic mode is effectively restrained, and the obtained high-purity target mode can be used for cold measuring of a gyrotron interaction circuit and a standard light mode converter system.

Description

Waveguide mode exciting bank

Technical field

The present invention relates to electron trade vacuum electronics technical field, relate in particular to a kind of waveguide mode exciting bank.

Background technology

Gyrotron has the advantages such as high power, long pulse, continuous wave output in millimere-wave band, in the fields such as plasma heating, material processed and biomedicine of millimetre-wave radar, controlled thermonuclear fusion, be with a wide range of applications.

Gyrotron adopts cavity that size is larger as interaction circuit in order to improve power capacity conventionally; and be operated in high-order side corner mould or high-order body mould, the higher order mode of gyrotron work need to be transformed to the low step mode of being convenient to transmission or directly utilizing through quasi-Optical Mode Converter.The high frequency interaction circuit of this class gyrotron and quasi-Optical Mode Converter system thereof conventionally need to be carried out cold survey before installing, and in cold survey, needed to encourage highly purified target pattern as the input signal of device under test.

Traditional mode excitation device adopts the method for quasi-optical mode excitation, higher to device fabrication required precision, also needs all parts accurately to aim in assembling process simultaneously, higher to requirement for experiment condition.

Summary of the invention

(1) technical problem that will solve

In view of above-mentioned technical problem, the invention provides a kind of to device fabrication precision and the lower waveguide mode exciting bank of requirement for experiment condition.

(2) technical scheme

According to an aspect of the present invention, provide a kind of waveguide mode exciting bank.This waveguide mode exciting bank comprises: first mode conversion assembly, and for realizing millimeter wave by TE ₁₀basic mode is to circular waveguide TE ₆₁the conversion of pattern; And the second mode conversion assembly, be connected with described first mode conversion assembly, for realizing millimeter wave by circular waveguide TE ₆₁pattern is to circular waveguide TE _6,2the conversion of pattern.

(3) beneficial effect

Waveguide mode exciting bank of the present invention is by rectangular waveguide TE ₁₀mould is to circular waveguide TE _6,2the conversion of the mode conversion chain of mould, has obtained highly purified target pattern output, has effectively suppressed parasitic mode, and the high-purity target pattern obtaining can be for the cold survey of gyrotron interaction circuit and quasi-Optical Mode Converter system thereof.

Accompanying drawing explanation

Fig. 1 is TE ₆₂the mode excitation flow chart of mould waveguide mode incentive structure;

Fig. 2 is rectangular waveguide TE ₁₀mould is to circular waveguide TE ₆₁the structural representation of the first mode conversion assembly of pattern;

Fig. 3 is circular waveguide TE ₆₁mould is to circular waveguide TE ₆₂the structural representation of the second mode conversion assembly of pattern;

Fig. 4 is TE ₆₂mould waveguide mode incentive structure internal field shape excitation schematic diagram;

Fig. 5 (a) is the TE of circular waveguide port standard ₆₂ideograph;

The output port place TE of Fig. 5 (b) for adopting the present invention to obtain ₆₂ideograph.

Embodiment

For making the object, technical solutions and advantages of the present invention clearer, below in conjunction with specific embodiment, and with reference to accompanying drawing, the present invention is described in more detail.It should be noted that, in accompanying drawing or specification description, similar or identical part is all used identical figure number.The implementation that does not illustrate in accompanying drawing or describe is form known to a person of ordinary skill in the art in affiliated technical field.In addition, although the demonstration of the parameter that comprises particular value can be provided herein, should be appreciated that, parameter is without definitely equaling corresponding value, but can in acceptable error margin or design constraint, be similar to corresponding value.The direction term of mentioning in embodiment, such as " on ", D score, 'fornt', 'back', " left side ", " right side " etc., be only the direction with reference to accompanying drawing.Therefore, the direction term of use is to be not used for limiting the scope of the invention for explanation.

In one exemplary embodiment of the present invention, provide a kind of waveguide mode exciting bank.The present embodiment waveguide mode exciting bank is realized by rectangular waveguide TE ₁₀pattern is to circular waveguide TE ₆₂the conversion of pattern.Wherein, TE ₆₂the mode excitation flow process of pattern as shown in Figure 1, that is: rectangular waveguide TE ₁₀pattern → coaxial waveguide TE ₆₁pattern → circular waveguide TE ₆₁pattern → circular waveguide TE ₆₂pattern.Wherein, the waveguide mode exciting bank of the present embodiment comprises: rectangular waveguide TE ₁₀pattern is to circular waveguide TE ₆₁the first mode conversion assembly of pattern and circular waveguide TE _6,1pattern is to circular waveguide TE _6,2second mode conversion assembly two parts of pattern.Below first mode conversion assembly and the second mode conversion assembly are elaborated respectively.

1, first mode conversion assembly

Fig. 2 is rectangular waveguide TE ₁₀pattern is to circular waveguide TE ₆₁the structural representation of the first mode conversion assembly of pattern.As shown in Figure 2, rectangular waveguide mainly comprises to the first mode conversion assembly of circular waveguide:

1.1 standard rectangular waveguides, waveguide dimensions adopts W wave band standard waveguide (waveguide dimensions: width edge length 2.54mm, narrow edge lengths 1.27mm), to transmit the TE of this W wave band ₁₀basic mode; The FUGP900 flange that the upper port of this standard rectangular waveguide adopts standard, docks for the FUGP900 flange with power source, as shown in Figure 2.

1.2 coaxial waveguides, coaxial waveguide is comprised of inner wire and outer conductor.This coaxial waveguide is divided into two sections-even section and transition.

In even section, the blind flange that passes on left of coaxial waveguide seals, and it comprises: outer conductor and the inner wire coaxial with this outer conductor, wherein, the internal diameter R of outer conductor _bfor 4mm, the external diameter R of inner wire _afor 2.5mm, this even segment length L ₁for 9.85mm.Outer conductor and standard rectangular waveguide are integrated by being welded and fixed, outer conductor communicates with standard rectangular waveguide by the coupling slot of sidewall, the shape and size of coupling slot are identical with standard rectangular waveguide, and the long limit of coupling slot and standard rectangular waveguide and the axially parallel of coaxial waveguide.

At non-homogeneous section, keep inner wire radius constant, it is large that the internal diameter of coaxial outer conductor becomes continuously, the length L of non-homogeneous section ₂for 55mm, the internal diameter R of outer conductor ₀for 8.5mm.At the end of non-homogeneous section, the internal diameter R of outer conductor ₀with the ratio 8.5/2.5=3.4 of the external diameter of inner wire, now, inner wire can be ignored, thereby realizes coaxial waveguide to the transition of circular waveguide, and excitation produces circular waveguide TE ₆₁pattern.

2, the second mode conversion assembly

Fig. 3 is circular waveguide TE ₆₁pattern is to circular waveguide TE ₆₂the structural representation of the second mode conversion assembly of pattern.As shown in Figure 3, the second mode conversion assembly is the circular waveguide of waveguide radius axial-periodic disturbance, and its front end is connected to the end of first mode conversion assembly by nonstandard of flanges, and its end is connected with other parts.The circular waveguide TE that this circular waveguide produces the excitation of first mode conversion assembly ₆₁mode conversion is circular waveguide TE ₆₂pattern.The profile function of the circular waveguide of waveguide radius axial-periodic disturbance is:

$a\left(z\right)=\frac{a_0[1-{\mathrm{\ϵ}}_0\cos (2\mathrm{\πz}/{\mathrm{\λ}}_W)-{\mathrm{\ϵ}}_1\cos (4\mathrm{\πz}/{\mathrm{\λ}}_W)]}{1-{\mathrm{\ϵ}}_0-{\mathrm{\ϵ}}_1}---\left(1\right)$

In formula, the axial length that z is circular waveguide, a (z) is is the circular waveguide internal diameter at z place in axial coordinate, a ₀for initial radium, i.e. the radius of the non-homogeneous end of coaxial waveguide in first mode conversion assembly, ε ₀and ε ₁for disturbance parameter, λ _wfor the disturbance cycle.In this example, the initial radium of circular waveguide is 8.5mm, relatively perturbation amplitude ε ₀=0.0536, ε ₁=0.008, disturbance cycle λ _w=20.6mm.

It should be noted that, above-mentioned parameter is only that example is practical, and those skilled in the art can design relevant parameter as required: Relative Perturbation amplitude, 0.001≤ε ₀≤ 0.1,0.001≤ε ₀≤ 0.1, disturbance cycle 10mm≤λ _w≤ 80mm.

Utilize the perturbation of this radius axial-periodic waveguide can by input circular waveguide TE ₆₁mode conversion is to TE ₆₂pattern, as shown in Figure 3.

As shown in Figure 4, the processing of total Plays rectangular waveguide, coaxial waveguide and circular waveguide all adopts oxygenless copper material to the schematic diagram of the fields inside shape excitation of the present embodiment waveguide mode exciting bank, and to the gold-plated processing of its inner surface to reduce the wastage.

Please refer to Fig. 1, Fig. 2 and Fig. 3, the operation principle of the present embodiment waveguide mode exciting bank is as follows:

(1) power source sends TE ₁₀the millimeter wave of basic mode;

(2) this TE ₁₀the millimeter wave of basic mode enters in standard rectangular waveguide by FUGP900 flange;

(3) TE in standard rectangular waveguide ₁₀the millimeter wave of basic mode is by even section of sidewall feed-in coaxial waveguide, and coupling produces coaxial TE ₆₁pattern;

(4) at non-homogeneous section, the coaxial TE being produced by even section of coupling ₆₁the millimeter wave of pattern is converted to circular waveguide TE ₆₁pattern;

(5), in the second mode conversion assembly, by introducing the disturbance of waveguide radius axial-periodic, realize millimeter wave by circular waveguide TE ₆₁pattern is to circular waveguide TE ₆₂the conversion of pattern.

Fig. 5 (a) is the TE of circular waveguide port standard ₆₂ideograph, the output port place TE of Fig. 5 (b) for adopting this example to obtain ₆₂ideograph.

So far, by reference to the accompanying drawings to the present embodiment millimeter wave TE _6,2the waveguide mode exciting bank of the cold survey of mould gyrotron have been described in detail.According to above, describe, those skilled in the art should have clearly understanding for waveguide mode exciting bank to the present invention.

In addition, the above-mentioned definition to each element and method is not limited in various concrete structures, shape or the mode of mentioning in embodiment, and those of ordinary skills can change simply or replace it, for example:

(1) standard rectangular waveguide, coaxial waveguide and circular waveguide also can adopt aluminium or brass to replace oxygenless copper material;

(2) nonstandard of flanges can replace with the standard flange of suitable specification;

(3) the present invention is except for millimeter wave TE _6,2outside the cold survey of pattern gyrotron, can also be applied to other field.

In sum, the present invention can be used for encouraging generation circular waveguide TE _6,2pattern, adopts this mode excitation structure can obtain the target pattern of high-purity, high efficiency, good stability.

Above-described specific embodiment; object of the present invention, technical scheme and beneficial effect are further described; institute is understood that; the foregoing is only specific embodiments of the invention; be not limited to the present invention; within the spirit and principles in the present invention all, any modification of making, be equal to replacement, improvement etc., within all should being included in protection scope of the present invention.

Claims (10)

1. a waveguide mode exciting bank, is characterized in that, comprising:

First mode conversion assembly, for realizing millimeter wave by TE ₁₀basic mode is to circular waveguide TE ₆₁the conversion of pattern; And

The second mode conversion assembly, is connected with described first mode conversion assembly, for realizing millimeter wave by circular waveguide TE ₆₁pattern is to circular waveguide TE _6,2the conversion of pattern.

2. waveguide mode exciting bank according to claim 1, is characterized in that, described first mode conversion assembly comprises:

Rectangular waveguide, is connected with power source, the TE producing for through-put power source ₁₀basic mode;

Coaxial waveguide, its one end is sealed by blind flange, and the other end is communicated to the second mode conversion assembly, and it is divided into two sections-even section and non-homogeneous section, wherein:

Evenly one end and the described rectangular waveguide of the sealing of section coaxial waveguide are welded as a whole, its outer conductor communicates with rectangular waveguide by the coupling slot of sidewall, the shape and size of this coupling slot are identical with described rectangular waveguide, and the long limit of described coupling slot and rectangular waveguide is with the axially parallel of coaxial waveguide, and millimeter wave is by TE ₁₀basic mode is converted to coaxial TE ₆₁pattern;

The inner conductor outer diameter of non-homogeneous section of coaxial waveguide remains unchanged, and it is large that outer conductor internal diameter becomes continuously, realizes coaxial waveguide to the transition of circular waveguide, and millimeter wave is by coaxial TE ₆₁pattern is converted to circular waveguide TE ₆₁pattern.

3. waveguide mode exciting bank according to claim 2, is characterized in that:

The length L of described even section of coaxial waveguide ₁for 9.85mm, the internal diameter R of its outer conductor _bfor 4mm, the external diameter R of inner wire _afor 2.5mm;

The length L of described non-homogeneous section of coaxial waveguide ₂for 55mm, at its front end, the internal diameter R of outer conductor _bfor 4mm, the external diameter R of inner wire _afor 2.5mm; At its end, the internal diameter R of outer conductor ₀for 8.5mm, the external diameter R of inner wire _afor 2.5mm.

4. waveguide mode exciting bank according to claim 2, is characterized in that, described rectangular waveguide is the waveguide of W waveguide standard, and its upper port adopts FUGP900 flange to be connected to power source.

5. waveguide mode exciting bank according to claim 2, is characterized in that, described the second mode conversion assembly is the circular waveguide of waveguide radius axial-periodic disturbance, and its front end is connected to the end of first mode conversion assembly, its end output circular waveguide TE _6,2the millimeter wave of pattern.

6. waveguide mode exciting bank according to claim 5, is characterized in that, the profile function of the circular waveguide of described waveguide radius axial-periodic disturbance is:

$a\left(z\right)=\frac{a_0[1-{\mathrm{\ϵ}}_0\cos (2\mathrm{\πz}/{\mathrm{\λ}}_W)-{\mathrm{\ϵ}}_1\cos (4\mathrm{\πz}/{\mathrm{\λ}}_W)]}{1-{\mathrm{\ϵ}}_0-{\mathrm{\ϵ}}_1}$

Wherein, the axial length that z is circular waveguide, a (z) is is the circular waveguide internal diameter at z place in axial coordinate, a ₀for initial radium, i.e. the radius of first mode conversion assembly end, ε ₀and ε ₁for disturbance parameter, λ _wfor the disturbance cycle.

7. waveguide mode exciting bank according to claim 6, is characterized in that, described disturbance parameter and disturbance cycle meet: 0.001≤ε ₀≤ 0.1,0.001≤ε ₁≤ 0.1,10mm≤λ _w≤ 80mm.

8. waveguide mode exciting bank according to claim 7, is characterized in that ε ₀=0.0536, ε ₁=0.008, λ _w=20.6mm.

9. waveguide mode exciting bank according to claim 5, is characterized in that, one of them is prepared from by following material for described rectangular waveguide, coaxial waveguide and circular waveguide: oxygen-free copper, aluminium and brass.

10. according to the waveguide mode exciting bank described in any one in claim 1 to 9, it is characterized in that, for millimeter wave TE _6,2the cold survey of mould gyrotron.