DE1766322A1 - Arrangement for holding a diode in a waveguide - Google Patents

Description

Dipl.-Ing. Heinz Ciaessen

Patent attorney

: 7 Stuttgart - Peuerbach
Short street 8

ISE-Reg. 3865
GPCraven l6

INTERNATIONAL STANDARD ELECTRIC CORPORATI (Ai, 520 Park Avenue, NEW YORK 22, N.Y., USA.

Arrangement for holding a diode in a waveguide

The priority of application number 22 147/6? in Great Britain of May 12, 1967 is used.

The invention relates to an arrangement for holding a diode in a waveguide which is attached to a waveguide arrangement is connected according to the type of attenuation and adapted to this.

A waveguide according to the attenuation type has a positive imaginary one Characteristic impedance (negative, imaginary wave admittance) and the port extension constant is real. the full transmission of energy through a waveguide of finite length below the cutoff frequency can be done by a terminating impedance with the conjugate value of the characteristic impedance of the waveguide is provided according to the attenuation type will.

The reflection-free energy transfer through waveguides according to the type of cushioning is described in British Patent Applications No. 643 279 (Application J 34 944 IXd / 21g), 67I 046 (Application J 33 854 ECd / 21g) and 681 637 (registration J 35 05I IXd / 21g) described.

In the arrangements according to these applications, band filters according to the attenuation type are used at the input and output by conventional

ZT / P OrPf (II) pie-krä.

April 30, 1968 109827/1248 " ² "

Waveguides completed for advancing waves * However, the conditions that apply to waveguides after the Have attenuation type set up, also applicable for networks that do not serve as filters. It follows that there is no need to terminate a continuing waveguide if there is a suitable transformation element between the filter (or another link) and the load is located. The cross-sections of waveguides for the advancing wave type are sometimes twice as large as that of a waveguide according to the attenuation type, which has the advantage of a smaller volume to need is lost again. Furthermore, an inductive susceptance value arises at the junction of these hollow core types, which has to be compensated. When components are used that combine with filters according to the type of attenuation there are some advantages.

A diode holder is one of the most important components that is also required in waveguides according to the attenuation type. The use of a diode holder in such a waveguide can be achieved by applying the customary adjustment measures enable, however, this results in a flow of energy. Furthermore, reflection occurs because the diode the impedance of the connected waveguide component, such as a filter, is loaded bring about the correct adjustment yourself.

The invention is based on the object of such a diode shark to create change.

The invention is characterized in that the holder the diode serving waveguide, which works for the operating frequency according to the damping type, a first, with a has capacitive shunt provided section from the input to the diode, the length of which is such that the input conductance is adapted to the conductance of the source and has a second section short-circuited at the end,

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109827/12 48

which represents an inductive reactance through which the capacitive reactance of the diode is compensated.

Embodiments of the arrangement according to the invention are described below with reference to FIGS. 1 to 7.

Fig.l and 2 show in section the side view and the Top view of a diode holder which is built into a waveguide according to the attenuation type.

Fig. 3 shows the equivalent circuit diagram of a diode, which is in a short-circuited waveguide piece is located according to the attenuation type.

4 shows a transformation network for the circuit according to Fig. 3.

Fig.5 shows a diode holder, which is in a waveguide after the attenuation type, which forms the conclusion of a band filter according to the attenuation type.

Fig.6 shows the plan view of a diode holder, the located in a waveguide according to the attenuation type.

Fig.? shows the side view of a conventional diode ' bracket that was changed to terminate a 4 GHz waveguide.

It can be seen from FIGS. 1 and 2 how a ceramic diode holder 1 is installed in a rectangular waveguide 2 is. The contact pin 3 egg holder 1 protrudes through a opening of the wall of the waveguide and is outside it ^ ben attached by a conductive piece 4. The contact 5 of the holder is separated from the waveguide by an insulating sleeve 6 .

There is a tuning screw 7 to the left of the diode and a coupling flange 8. Right next to the diode ± fit one short-circuited waveguide section 9 attached. The height and the width of the waveguide are dimensioned so that this

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at the operating frequency according to the damping type, i.e. works below the limit frequency. For one operating frequency of 40 Hz, the waveguide has a height of approx. 10 mm and a width of approx. 25 mm.

A diode, which is built into a short-circuited section of a waveguide according to the attenuation type, can be represented according to the equivalent circuit diagram of Pig. 3 as a shunt resistor bridged by a capacitance, which is at a distance t ^ from the terminal T of the transmission line. This has the waveguide value Y, which is negative imaginary and has a real port planting constant Y ~ .

The admittance Y _{1 of} the diode is

Y ₁ - 0 + JB (1)

where 0 is the real conductance and B is the susceptibility of the diode. The admittance value Yg of the short-circuited section I ₂ is

Y ₂ - -JY ₀ coth ^ Z ₂ {2)

it follows that

Y ₁ + Y ₂ - 0 + j (BY ₀ coth rt _Z ) O)

, is chosen so that (B -Y _n coth γ · -C ) -oTst. This means that the inductive reactance of the short-circuited part of the waveguide compensates for the capacitive reactance of the diode, so that Y ₁ + Y ₂ «0. Thus, only the effective resistance of the diode needs to be taken into account. The equivalent circuit diagram according to FIG. 4 shows a transformer element which has an input solenoid input value Y * at terminal T.

In the case of resonance, the input conductance value O ₁ results in Y _n QOBh ² TA + v ^eln » ^£

109827/1248 - 5 -

The adaptation of the input conductance G ₁ to the conductance of $ μβ11β is done by appropriately dimensioning the length Ji-,.

The resonance condition can be determined from the imaginary part of Y. and the input susceptance _{B., where -JY 0} (G ^ + Yp

B ₁ = -yg. (5)

Y * coth T JL ₁ + 0 tanh YJ ₁

In order to be able to tune out this inductive _{susceptibility value B 1} , 3ab a capacitive susceptance value B _{1 applied} via the connection T.

The value of G ₁ decreases with an increase in γ · J- ^ . Therefore a low diode impedance and a high source impedance require a relatively high value for y * -c ...

This method of fitting a load where the distance between the load and the source is the fitting parameter differs fundamentally from conventional line technology. The impedance transformation increases steadily with the distance between source and load and does not follow the cyclical representation, which is for ladder for progressive Waves.

If a waveguide filter is to be terminated with a Οίοι de according to the attenuation type, it is adapted according to FIG. 5 by a suitable choice of the distance <£, between the diode and the last tuning screw of the filter. The value of B ₁ can then be tuned out using this screw. The susceptibility of the diode is, as already described, compensated by attaching the short circuit for the waveguide after the diode at a suitable distance ^ ₂ .

f. If the value O _{1 is assigned to} the diode and the value G to the source, then expression (4) gives the impedance transformation

in the opposite direction. The value B ₁ must then be on the diode * and can be tuned out by its stray capacitance. Is ^: 109827/1 248

ISE-Reg. 3863 -6- 17RR ^ 9?

if this is not big enough, there is an additional tuning screw 10 (Fig. 6) to be provided.

Instead of a ceramic diode holder, which is inserted directly into the waveguide according to FIGS. 1 and 2, it is also possible to use a coaxial diode holder. FIG. 7 shows a holder of this type on a 4 Ω Hz Hohilter with a screw 11 for tuning out the inductive susceptance value of the diode holder. Since the waveguide works according to the attenuation type at the operating frequency, the lengths Jt--, and L ^ are determined with the help of the relationships given above. The short-circuited section of the hollow core compensates for the capacitive susceptance of the diode

6 claims

1 sheet drawing. (7 fig.)

109827/1248

Claims (6)

Claims 1. Arrangement for holding a diode in a waveguide, which is connected to a waveguide arrangement according to the attenuation type and adapted to this, thereby geke η, η ζ ei without t that the hollow conductor serving to hold the diode, which for the operating frequency after Attenuation type works, has a first, provided with a capacitive shunt section ( Zx ) from the input to the diode, the length of which is such that the input conductance is adapted to the conductance of the source and a second section short-circuited at the end (^ ₂ ) which represents an inductive reactance through which the capacitive reactance of the diode is compensated. 2. Arrangement according to claim 1, characterized in that the capacitive shunt at the entrance of the first section is located. j5. Arrangement according to claim 1, characterized in that the capacitive shunt of the first section is at the diode. 4. Arrangement according to claims 1 to J5, characterized in that that the capacitive shunt has a tuning screw. 5. Arrangement according to claims 1 to 4, characterized in that the diode is in the waveguide section is located. 6. Arrangement according to claims 1 to 4, characterized in that the diode is coaxial in the waveguide section is coupled. ZT / P OrPf <II) ple-krä.
April 50, 1968 109827/1248