SU1241309A1 - Microwave selector switch - Google Patents

Abstract

The invention relates to a microwave technique and can be used in installations forming high-power microwave signals of nanosecond duration, as well as in high-power PJK antenna switches. Switching and recovery times are reduced. The device contains a waveguide tee (W) with a short-circuited shoulder and with an opening 4 in a wide wall in which the ignition electrode (PE) 5 is placed, a short-circuiting wall, a dielectric rod DS) 6 and a lens. 7, placed coaxially with PE 5 outside W. When applying for PE 5 shears. the ignition voltage pulse between the PE 5 and the edge of the hole 4 ignites the spark discharge, which is a source of free electrons and ionizing UV radiation. Lens 7, reflector UV radiation, generates a UV discharge directed along the discharge gap. A part of the energy of this radiation, which was not spent on the photoionization of gas, reflected from DS 6, again participates in photoionization. The goal is achieved by introducing the DS 6 and lens 7. 1 CI f-ly, 2 ill. with Jbl fSS 4M (put. 2

Description

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The invention relates to a microwave technique and is intended for use in installations generating high-power microwave pulses of nanosecond duration, as well as in antenna switches of high-power radar stations.

The purpose of the invention is to reduce switching time and recovery.

FIG. 1 is shown. The RF switch in FIG. 2, section A-A in FIG. one .

The microwave switch contains, waveguide tee 1, short-circuited, shoulder 2 of the bifurcated tee 1, short-circuit wall 3, hole 4, igniting electrode 5, dielectric rod 6, lens 7 reflecting ultraviolet radiation,

The device works as follows. . ,

In the initial state in the arm 2 of the tee 1, an electromagnetic field of a high power level in the form of a standing wave is excited. At the desired time, a negative igniting voltage pulse is applied to the electrode 5. Between the electrode 5 and the edge of the hole 4, a spark is ignited, which is a source of free electrons and ionizing ultraviolet radiation. Lens 7 forms a nyciKOBoro discharge ultraviolet radiation directed along the discharge gap. A part of the energy of this radiation, which has not been spent on photoionization, is reflected, from the dielectric rod 6, and re-participates in the frenchionization. Since the dielectric STERN 6 from the point of view of electrical strength is the weakest point of the device, therefore, due to intense illumination with ultraviolet radiation, a discharge begins to develop on its surface, which forms a plasma with a high emission ability. As a result, formed on the surface of the dielectric, and the start-up plasma j, as well as a strong photoionization of the discharge gap between the hole 4 and the rod 6, a plasma column CB is formed H-razr yes ..

Plasma column of a gas microwave discharge with some approximation

ten

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20

25

241309 "

gick capacitive pin. If the length of the capacitive pin / 4, where 7i is the wavelength in free space, then this is equivalent to a short circuit of the waveguide. Therefore, the dielectric rod 6 is enough to be placed in the waveguide at a distance from the axis of the rod 6 to the wide wall of the arm 2; approximately equal to where R is p; zdius of the rod 6 .. By means of this reduction, the ultraviolet radiation energy loss due to diffraction.

The time of formation of the microwave discharge depends on the degree of homogeneity of the floor. Dielectric materials due to radio transparency for electromagnetic waves introduce smaller distortions of the field 5 than metals, therefore the rod 6 must be made of a dielectric mat. In order not to distort the floor, due to the non-uniform surface of the rod 6, it is shaped into a cylinder of radius R. This increases the electrical strength of the microwave switch, which is important both for controlling the switching process and increasing the level of the power switches.

The larger the plasma surface, the higher its emission properties, therefore, the dielectric rod 6 should be as large as possible. However, an increase in the diameter of the rod b leads to a decrease in the electrical strength of the gap between its surface and the wide wall of the waveguide. Consequently, the choice of a 1 meter dielectric 40 rod 6 is determined by the possibility of providing the necessary electrical strength of the device.

An increase in the rate of development of the paS-row over the surface of the dielectric is proportional to the increase in the dielectric constant of the material from which it is made. Therefore, a material with a high dielectric constant should be used to fabricate the dielectric rod 6.

In addition, an electromagnetic wave experiences complete reflection from the interface between two dielectric media with a complete mismatch of the wave resistances of these media. Therefore, in order for the dielectric rod fe to have a high reflection coefficient of ultraviolet

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rays should be made of a material with a higher dielectric constant than the medium filling the discharge volume.

Thus, using the proposed switch, by reducing the switching time and recovery time, microwave pulses with a duration of 0.5 amplitude 13 can be formed not by filling the discharge volume with gaseous nitrogen.

F o rm ula invention

Claims (1)

1. The microwave switch containing a waveguide tee, the asymmetrical arm of which is short-circuited and in its wide wall at a distance of L / 4 from the short-closing wall is filled with an opening in which the igniting 41309 4 an electrode, distinguished by the fact that, in order to reduce the switching time and restoration, a 2K diameter dielectric was inserted into it, made from a material with a high dielectric constant, which is installed in the same transverse plane with a burning electrode between narrow 10 by the walls of a short-circuited plbcha waveguide tee at a distance equal to ft / 4 + R from its wide wall in which a hole is made, where L is the working wavelength 5 waveguide tee. 2, the microwave switch according to claim 1, characterized in that a lens is inserted therein that reflects ultraviolet radiation, which 20 is placed coaxially with the ignition electrode outside the waveguide tee. Compiled by S. Shishchuk Editor M. Dylyn Tehred N. Bonkalo Proofreader E. Roshko Order 3604/47 Circulation 597 Subscription VNIIPI USSR State Committee for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab, 4/5 Production and printing company, Uzhgorod, st. Project, 4 1