RU1807538C - Open resonator - Google Patents

Abstract

The invention relates to microwave technology and can be used as frequency selective path circuits. The purpose of the invention is to provide a spatial separation of two closely spaced operating modes of vibration. An open resonator comprises a section of a dielectric waveguide, located between two metal mirrors (MZ) provided with at least one coupling element. Between the metal mirrors a second identical segment of the dielectric waveguide and additional communication elements placed on the MZ are introduced. The first and second EFA are made flat and installed at an angle m r one above the other, and their axes lie in the same plane. The thickness d of these EFAs and the distance dc between them in the middle between the MZs are selected from conditions that relate the geometry parameters (d, dc, p) and the parameters of dielectric materials with an average wavelength and resonant frequencies of two working modes of vibration that are close in frequency. Thanks to the introduction of the second EFA and its placement, as well as the fulfillment of the restrictive conditions, the EFA communication is irregular, which ensures the spatial separation of two working modes of oscillations close to the resonant frequencies and the possibility of separate adjustment of their external links to the MZ. 1 ill. (L

Description

The invention relates to microwave technology, namely to resonant devices, and can find application in communication systems, radar, devices for non-destructive testing of materials, as well as in other areas where means of transmission, reception and processing of information in millimeter and submillimeter (mm and submm) wavelength ranges.

It is an object of the present invention to provide a spatial separation of two adjacent frequency modes of operation.

This goal is achieved by the fact that a second identical segment of the dielectric waveguide is introduced into the well-known open resonator containing a segment of a dielectric waveguide located between two metal mirrors, equipped with at least one coupling element, and the first and second segments of the dielectric waveguide are made in plan and mounted one above the other at an angle p, with their longitudinal axes lying in the same plane, and the thickness d of the segments of the dielectric waveguide and the distance dc between them in the middle between metal mirrors are selected from the conditions

00

about M

ate

00

00

d Ap / 2V

(1)

 -Kin

. i l r-f-h YA ba ....: U, -

Or - MGTPlz --- r i- J о ...- .., tg .r iznriz.-. VKzi. - Kot2 g 1Gk; G t2 kTp. tg (- KЈ d) +

rrrVKln -KG

r-T-fJT-5 ,.

 -Kin

 ba ....: U, -

...- .., tg .r iznriz.-. . tg (- KЈ d) +

rrrVKln -KG.

r-T-fJT-5 ,. W

y 2arctg

(3)

2l:

where Ap 2c / (f 1 + f2), Ko Ј, Kzn

2llЈ

c is the speed of light in vacuum, Ap is the average resonance wavelength of the working modes of vibration with frequencies fi and fa, L is the length of the segments of the dielectric waveguide, m and

 the refractive index and dielectric constant of their material, respectively.

According to the analysis of patent and scientific and technical literature, the authors are not aware of works that describe or use an open resonator with two identical planar segments of a dielectric waveguide mounted at an angle to each other between metal mirrors, which provides a spatial separation of two frequency-related working types fluctuations. Theoretical and experimental work on the spatial-frequency splitting of fields in such a resonator is also unknown.

A positive effect in the present invention is achieved due to the fact that, at the selected sizes of the waveguide segments and their relative positions according to expressions (1) - (3), such even system interacts its even and odd vibrations with different longitudinal indices n and n-1, which degenerate in frequency at (p 0. Condition (1) determines single-mode

dc -

UKTP-K

Mr. Arth

 - Kg tg (Vm2K d) - m2VK | n - KJ5 - KЈ tg (- к | п d) + Vm2K +

(p 2arctg

2l

2lUe

where Ap 2c / (f + fa), Ko-r, Krp

lr- -,

c is the speed of light in vacuum, Ap is the average resonance wavelength of the working modes of vibration with frequencies fi and fa, L is the length of the segments of the dielectric waveguide 1 and 2,

m and k are the refractive index and permittivity of their material, respectively.

sections in a dielectric waveguide in cross section, which in combination with other features works to achieve a positive effect. Expression for

Q dc (2), Ap, Co, KZn determine the coincidence points of the frequencies of the n-th even and (n-1) -th odd oscillations of the proposed resonator. The introduction of the angle (p between the segments of the waveguides leads to their resonant tuning.

5 Two working modes of oscillation are formed with close frequencies fi and fa, the field of which is not. coupled and spatially separated on metal mirrors, which is not possible in the prototype. This is discovered by the authors for the first time. The limit of variation (f according to (3) corresponds to the extreme position of the slope of one segment of the waveguide to another, i.e. this condition follows from the design of the resonator. Changing the angle p according to (3) regulates the separation between fi and fa.

In the drawing, a schematic representation of the proposed resonator.

The proposed open resonator contains the first 1 and second 2 identical segments of a planar dielectric waveguide, metal mirrors 3 and 4. The segments of the dielectric waveguide 1 and 2 are mounted one above the other at an angle (p, with their longitudinal axes 5 and 6 lying in the same plane. Thickness d of segments of the dielectric waveguide 1 and 2 and the distance dc between them in the middle between the metal mirrors are selected from the conditions:

0

5

0

5

40

d An / 2V

0

5

The coupling element, for example, in the form of a rectangular hole 7 is made symmetrically with respect to the axis of symmetry 8 of the system at (p 0. The communication element, for example, in the form of rectangular hole holes 9 and 10. are made symmetrically in the mirror 4, axis 5 and 6 segments of the waveguide 1 and 2.

The proposed open resonator operates as follows. A high-frequency signal including adjacent frequencies fi and fa is supplied through the communication hole 7 to it. For the selected thickness d of the segments of the dielectric waveguide 1 and 2, the distance dc between them in the middle between the orcs 3 and 4 and the angle y, under which the segments 1 and 2 are installed, vibrations with frequencies fi and Λ are excited in it. These oscillations are the result of the interaction of two oscillations degenerate at p 0 at the frequency

fp -Ј (fi + f2) / 2: even and odd

WITH

oscillations of the system of two segments of the waveguide 1 and 2 and having different longitudinal indices n and (n-1), where n is the number of half-waves in the system along L, Each of the oscillations with frequencies fi and fa can be represented as the spatial beat of waves forming a degenerate oscillation. Beats appear in the periodic pumping of field energy along L from one segment of the waveguide, for example, 1 to the second and vice versa. It has been experimentally established that powers corresponding to the frequencies fi and fa, .. are pumped in antiphase. As a result, on each of mirrors 3 and 4, the oscillation field of frequencies f 1 and h are localized over the ends of different segments of waveguide 1 and 2, i.e. spatial separation of two adjacent frequency modes of operation is provided. In this case, the spots of their fields on the mirrors 3 and 4 partially overlap in the region of the longitudinal axis of the system 8 so that they can be simultaneously excited, for example, through the communication hole 7 (Fig. 1), and output separately through two frequency channels f 1 and fa by means of, for example, communication holes 9 and 10. As the communication elements, translucent mirrors, mirrors in the form of metal gratings can be used.

and corresponding condition (2) for determining dc. The influence of heterogeneity in the structure leads to the removal of this degeneracy. We show this using the integral equation obtained from the Maxwell system of equations

((x) + H + n% Y

 w / AЈf nfdV (2n)

Here & Ј is the heterogeneity in the structure,

ft)

- ,,, g-t- ...- -rf - .. Jr, -,

and E, m - frequency and field strength

The invention is illustrated by the following example.

Due to the fact that the physicotechnical foundations of the proposed cutter are based on effects discovered theoretically and experimentally by the authors of the proposed technical solution for the first time and information about which is not available in the domestic and foreign literature, the description of the studies is compatible with the implementation example of the proposed device.

Solving the system of Maxwell equations and satisfying the conditions for the continuity of the fields at the interfaces of various structure media, we obtain a dispersion equation that determines the eigenfrequencies E of the oscillations (Ex, Eu, Well, the field components are nonzero):

КdKy - Kg tg (Kgd) - units

x (Kgd), (1P)

where tf - th (Kbdc / 2) - for even vibrations

ts with th (Ki dc / 2) - for odd vibrations

Kg and Ki are the transverse components of the wave vectors in dielectric and in vacuum, respectively.

From this equation it is easy to obtain an expression for cases of frequency degeneracy of even and odd vibrations with different longitudinal indices n and (n-1):

in the presence of heterogeneity, Шп and Еп, Нп - frequency and floor of one of the natural vibrations of the structure in the absence of heterogeneity. We represent Paul E and n as a superposition of these oscillations:

 "D E 1," And (Cn)

With small heterogeneity, the main terms in (2n) are terms describing the interaction of degenerate even and odd vibrations with adjacent longitudinal indices n and (n-1), leading to their splitting into two copecks with a small difference in frequency

Aft) ± ±, n 4- s Ln-L s,

.2 (4n)

rAeAnp T &: F-nEdV / Np

 (x) | Enl2dV T mn 2dV rate of oscillation. If the structure is heterogeneous due to the angle of inclination p between the segments of the waveguides De e-1, and integration is carried out over the space of the deviation of the segments from their parallelism. As a result, we can obtain the connection between the LOI

 ± WnF (K8, K9, e, d) -4L2 (A /) 2.

Experimental studies were carried out in the 8 mm wavelength range. Fragments of a dielectric waveguide of length L 12 cm and thickness d 7.0 mm of fluoroplastic-4 were used, which were installed between metal mirrors with communication holes of 7.0 x 0.1 mm2. At dc 0.7 mm, an interaction was observed between an even oscillation of the system with a longitudinal index of n 37 and an odd one with h 36. When placing the communication hole on the first mirror in the center of the system height and turning on the resonator, reflection resonances were observed with, 220 GHz and, 030 GHz . Af was controlled by a slight change in the angle of inclination (p 1 °. By studying the structure of the oscillation fields by the probe method, it was found that the energy i field with fi is localized on one mirror under the end face of the first waveguide segment and gradually passes along L into the second and vice versa. fa - vice versa

- When the resonator is turned on for passage in such a way that on the second mirror one communication hole is located in the end region of the first waveguide segment and the other is in the second, the signals with frequencies fi and fa are separated by two separate frequency channels, the paths of which are connected to the corresponding holes communication.

Thus, experimental studies confirm the positive effect, which was obtained on the basis of a previously unknown phenomenon of spatial frequency splitting of vibrations. The parameters of the fabricated resonator correspond to relations (1) - (3).

Consider the advantages of the proposed resonator compared to the prototype. With the selected parameters, it can support electromagnetic vibrations of the mm and submm ranges both at one or several resonant and at two close frequencies. Localization of the vibration fields with close frequencies occurs in

different places on the mirrors. This provides a spatial separation of two adjacent in frequency working modes of vibration, which is impossible in the prototype. The proposed resonator allows

spatially separate communication with each of the neighboring oscillation frequencies. This extends its functionality compared to the prototype: it is possible to extract (enter) filtered

signals of two channels with close frequencies, i.e. use as a frequency separation / combining filter. It can provide generation at two close frequencies with separate output of signals (a two-frequency generator with the possibility of frequency stabilization), mixing the frequencies of the signal and the local oscillator (mixer), etc., which cannot be directly performed by the prototype. The proposed resonator provides a positive effect in the mm and submm ranges, where the known cubic and complex dielectric resonators lose their functional properties,

Claims (1)

The claims An open resonator containing a segment of a dielectric waveguide located between two metal mirrors provided with at least one communication element, characterized in that, in order to ensure spatial separation of two adjacent operating frequency modes of oscillation, a second identical segment of the dielectric waveguide is introduced, the first and second dielectric waveguides are plenary and mounted one above the other at an angle (p, and their longitudinal axes lie in the same plane, and the thickness d of the segments of the dielectric waveguide and the distance dc between them in the middle between the metal mirrors are selected from the conditions  Ap / 2vST dc (1 / VK2n -Ko) Arth {f / m2Ko tgCvrr d) - m VRln - Kn) / tg () + + vrT KT + l &r}; p $ 2 arctg (dc / L), where Ap 2c / (fi + fz); K- Otg / 3 o fcfc t / Ap; Kzn 2ll / g / dr; c is the speed of light in vacuum. Dp is the average resonance wavelength of the working modes of vibration; L is the length of the segments of the dielectric waveguide: m and E are the refractive index and effective dielectric constant of their material, respectively.