EP0097112B1 - Hf adaptation transformer - Google Patents

Hf adaptation transformer Download PDF

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Publication number
EP0097112B1
EP0097112B1 EP83710019A EP83710019A EP0097112B1 EP 0097112 B1 EP0097112 B1 EP 0097112B1 EP 83710019 A EP83710019 A EP 83710019A EP 83710019 A EP83710019 A EP 83710019A EP 0097112 B1 EP0097112 B1 EP 0097112B1
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EP
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Prior art keywords
conductor
hollow cylinder
diameter step
inner conductor
outer conductor
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EP83710019A
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German (de)
French (fr)
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EP0097112A1 (en
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Wolfram Dr. Schminke
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BBC Brown Boveri AG Switzerland
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BBC Brown Boveri AG Switzerland
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01P—WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
    • H01P5/00—Coupling devices of the waveguide type
    • H01P5/04—Coupling devices of the waveguide type with variable factor of coupling

Definitions

  • the invention relates to an RF matching transformer in the form of a coaxial line with a fixed length according to the preamble of claim 1, 2 or 4.
  • a transformer is e.g. in US-A 2,408,745.
  • two-stage coaxial matching transformers with fixed transmission ratios have been used for a long time.
  • Such an adaptation transformer is known, for example, from the book by Meinke / Gundlach, "Taschenbuch der Hochfrequenztechnik", Springer Verlag Berlin / Heidelberg / New York, 111th edition 1968, pp. 384-365 as a two-stage ⁇ / 4 transformer. It consists of a waveguide, the total length of which is equal to half the wavelength of the operating frequency 2 ". It is divided into two 7" / 4 long conductor sections, the different wave resistances of which are determined by the connection impedances at the input and output, between which the adaptation is made should.
  • this transformer Since the length of this transformer is directly linked to the operating frequency, its dimensions can only be used for an operating frequency within a narrow frequency band.
  • the impedances of a coaxial line are also predetermined by the geometry, so that differently designed transformers are required for different adaptation cases.
  • variable matching transformers in a coaxial construction in which a conductive hollow cylinder which is displaceable in the direction of the conductor axis is arranged within a continuous coaxial line with constant conductor diameters.
  • This hollow cylinder together with the conductor pieces enclosing it, forms a line section of constant length and deviating wave resistance.
  • This conductor section connects two line sections adjoining on each side, the sum of their lengths being constant, and both of which have the characteristic impedance of the underlying coaxial line.
  • a differentially operating microwave phase shifter is known from CA-A 853 353, in which two waveguide pieces of different diameters are connected by a hollow cylinder section which can be displaced in the direction of the conductor axis in order to set a variable phase shift. If this hollow cylinder section is shifted, the phase shift of one waveguide section is reduced, while that of the other section is increased, so that a differential change occurs.
  • a working principle for a coaxial adaptation transformer that can be set within wide limits cannot therefore be obtained from the non-generic subject matter of this patent specification.
  • the present invention has for its object to provide a coaxial RF matching transformer, the working frequency and transmission ratio can be set continuously within wide limits without changing the installation dimensions of the transformer.
  • the matching transformer according to the invention which is designed as a coaxial line, consists of an outer conductor with a constant inner diameter and an inner conductor with stepped outer diameters, with a conductive hollow cylinder with correspondingly stepped diameters displaceable in the direction of the conductor axis being attached to the inner conductor and short-circuited with the inner conductor at least in terms of radio frequency is.
  • the matching transformer according to the invention has the advantage that its operating frequency can be changed without changing the overall length of the waveguide and thus the installation dimensions.
  • a specific transmission ratio is linked to the respective working frequency, so that there is a continuous, characteristic-like relationship between frequency and transmission ratio in the adjustable working range of the transformer.
  • This characteristic curve can be designed by a suitable choice of the geometric parameters so that it is adapted to the characteristic curves of other RF circuit elements. In this way, e.g. Build a continuously tunable HF generator if the impedance curve of the transmitter tube used corresponds to the characteristic of the connected transformer. Further embodiments of the invention are shown in the drawing and are explained in more detail below.
  • FIG. A waveguide W of length L is divided into at least two conductor sections W 1 and W 2 with different wave resistances Z and Z 2 .
  • the lengths L 1 and L 2 of the conductor sections can be adjusted in such a way that their sum L 1 + L 2 remains constant, ie the first length decreases by exactly the amount by which the second increases, and vice versa.
  • the transformer is loaded by a real terminating impedance Z A. This terminating impedance is transformed into a real input impedance Z E. This transformation takes place in several stages, according to the different ladder sections.
  • the conductor section W 2 first converts the real terminating impedance Z A into a generally complex intermediate impedance Z M , which in turn is transformed by the conductor section W into the real input impedance Z E. Since the transmission can be assumed to be damping-free in a first approximation, it obeys the transformation equation known from line theory
  • Fig. Shows a preferred embodiment of the matching transformer according to the invention.
  • a coaxial line is provided as the waveguide, which consists of an outer conductor 1 with a constant inner diameter D 1 and an inner conductor 2 with stepped outer diameters d 1 and d 2 .
  • a conductive hollow cylinder 3 is attached to the inner conductor 2.
  • the hollow cylinder 3 is displaceable in the direction of the conductor axis and graduated in diameter in the same way as the inner conductor 2. Its wall thickness is preferably so small compared to the other dimensions of the conductor that the properties of the inner conductor 2 are only slightly disturbed with respect to the wave propagation .
  • the hollow cylinder 3 can be made of thin sheet metal, for example, and can be coated with a highly conductive layer. It is particularly advantageous in terms of weight to use metallized plastics on the basis of, for example, glass fiber-reinforced epoxy resins for the hollow cylinder but also for the other conductors.
  • the hollow cylinder is preferably conductively connected to the inner conductor 2 at its ends via sliding contacts and thus forms a displaceable step on the inner conductor with regard to the wave propagation in the coaxial line. If the hollow cylinder 3 is moved, for example, to the position shown in dashed lines in FIG.
  • transmission ratios result in the transformer which no longer correspond to conductor sections with the lengths L 1 and L 2 , but with conductor sections with the new lengths L 1 'and L2', whereby Both the wave resistances Z 1 and Z 2 and the total length L remain unchanged.
  • the wave resistances Z 1 and Z 2 of the conductor sections also result from the diameters D 1 , d, and d 2 according to the formula known for the coaxial line whereby the influence of a possible dielectric between the outer and inner conductors is taken into account by the relative dielectric constant ⁇ r .
  • FIG. 3 Another embodiment of the matching transformer according to the invention is shown in FIG. 3.
  • the inner conductor 2 of the coaxial arrangement is again designed with stepped outer diameters d 1 and d 2 .
  • the outer conductor 1 also has stepped inner diameters D 2 and D 3 .
  • the diameter of the displaceable hollow cylinder 3 is adapted to the outer conductor 1 and short-circuited with it at least in terms of radio frequency, and thus forms a stepped outer conductor with a displaceable edge. This results in a coaxial line with at least three different conductor sections W 1 , W 2 and W 3 with the corresponding lengths L 1 , L 2 and L 3 as well as characteristic impedances Z 1 , Z 2 and Zg.
  • the hollow cylinder 3 can be displaced from the outside without disturbing the wave propagation, for example by leading out an operating element rigidly connected to the hollow cylinder 3 through a narrow slot in the outer conductor 1 and actuating it by a drive mechanism arranged outside the outer conductor 1.
  • a corresponding operating mechanism can also be provided in the exemplary embodiment shown in FIG. 4, in which the coaxial line is composed of an inner conductor 2 with stepped outer diameters d 1 and d 2 and an outer conductor 1 with a constant inner diameter D 1 .
  • the hollow cylinder 3 is adapted with its larger diameter to the inner diameter D 1 of the outer conductor 1 and provided with a smaller diameter D 4 , the size of which lies between the inner diameter D 1 of the outer conductor 1 and the largest outer diameter d 1 of the inner conductor. It is short-circuited to the outer conductor, at least in terms of radio frequency, and together with it forms an outer conductor with two edges which can be displaced in the same direction.
  • the coaxial line is divided into four conductor sections W 1 , W 2 , W 3 and W 4 with the lengths L 1 , L 2 , L 3 and L 4 and the characteristic impedances Z 1 , Z 2 , Z 3 and Z 4 .
  • the lengths of the conductor sections are changed as a function of one another by displacing the hollow cylinder 3, the length L 5 of the hollow cylinder 3 and the total length L of the coaxial line remaining constant.
  • the high-frequency short circuit between the hollow cylinder 3 and the adjacent conductor surface is not mediated in this exemplary embodiment by sliding contacts, but by a thin, dielectric film covering 5, which lies between the hollow cylinder 3 and the adjacent conductor surface.
  • the film covering 5 which consists for example of Teflon or Kapton, enables on the one hand an almost friction-free sliding of the displaceable hollow cylinder in the outer conductor 1.
  • the hollow cylinder and outer conductor together with the hollow cylinder and outer conductor, it forms coaxial line pieces 6 with very low impedance. It should be noted that the electrical length of the coaxial line pieces 6 is less than 1/4 of the corresponding wavelength ⁇ G at the highest operating frequency.
  • FIG. 5 shows the characteristic field of an adaptation transformer according to the invention in accordance with the exemplary embodiment shown in FIG. 2.
  • the pair of characteristics R 3 , f 3 is of particular importance for the application. It shows that the adaptation transformer according to the invention can be continuously tuned over a large frequency range of over 150 MHz with only a slight change in the transformation ratio by changing the length L 2 .
  • Corresponding characteristic curve fields also describe the operating behavior of the exemplary embodiments according to FIGS. 3 and 4.
  • the characteristic curve shown in FIG. 4 results for an arrangement according to FIG. 4.
  • matching transformers can be constructed according to the invention by suitable selection of the geometric and electrical parameters as well as by combination of several movable and fixed diameter stages on outer and / or inner conductors, the characteristics of which optimally correspond to the respective intended use in an HF circuit, and the characteristics of operating frequency and Transmission ratio can be changed continuously over a wide range without the need to remove and install the transformer itself.

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Description

Die Erfindung betrifft einen HF-Anpassungstransformator in Form einer Koaxialleitung mit einer festen Länge nach dem Oberbegriff des Anspruchs 1, 2 oder 4. Ein solcher Transformator ist z.B. in der US-A 2 408 745 beschrieben.The invention relates to an RF matching transformer in the form of a coaxial line with a fixed length according to the preamble of claim 1, 2 or 4. Such a transformer is e.g. in US-A 2,408,745.

Seit langem werden in der Praxis zweistufige koaxiale Anpassungstransformatoren mit festen Übertragungsverhältnissen verwendet. Ein solcher Anpassungstransformator ist beispielsweise aus dem Buch von Meinke/Gundlach, "Taschenbuch der Hochfrequenztechnik", Springer Verlag Berlin/Heidelberg/New York, 111. Auflage 1968, S. 384-365 als zweistufiger λ/4-Transformator bekannt. Er besteht aus einem Wellenleiter, dessen Gesamtlänge gleich der halben Wellenlänge der Betriebsfrequenz 2" ist. Er ist unterteilt in zwei 7"/4 lange Leiterabschnitte, deren unterschiedliche Wellenwiderstände durch die Anschlußimpedanzen an Ein- und Ausgang festgelegt werden, zwischen denen die Anpassung hergestellt werden soll. Da die Länge dieses Transformators direkt mit der Betriebsfrequenz verknüpft ist, kann er in seinen jeweiligen Abmessungen nur für eine Betriebsfrequenz innerhalb eines schmalen Frequenzbandes eingesetzt werden. Darüber hinaus sind bei einer Koaxialleitung durch die Geometrie auch die Wellenwiderstände vorgegeben, so daß für unterschiedliche Anpassungsfälle auch unterschiedlich ausgelegte Transformatoren benötigt werden.In practice, two-stage coaxial matching transformers with fixed transmission ratios have been used for a long time. Such an adaptation transformer is known, for example, from the book by Meinke / Gundlach, "Taschenbuch der Hochfrequenztechnik", Springer Verlag Berlin / Heidelberg / New York, 111th edition 1968, pp. 384-365 as a two-stage λ / 4 transformer. It consists of a waveguide, the total length of which is equal to half the wavelength of the operating frequency 2 ". It is divided into two 7" / 4 long conductor sections, the different wave resistances of which are determined by the connection impedances at the input and output, between which the adaptation is made should. Since the length of this transformer is directly linked to the operating frequency, its dimensions can only be used for an operating frequency within a narrow frequency band. In addition, the impedances of a coaxial line are also predetermined by the geometry, so that differently designed transformers are required for different adaptation cases.

Ändern sich daher in einer durchstimmbaren HF-Schaltung die Betriebsfrequenz und/oder die Impedanzverhältnisse in größerem Umfang, ist es notwendig, einen in die Schaltung eingefügten Transformator durch einen anderen mit veränderter Geometrie zu ersetzen. Dies führt, insbesondere in Leistungsschaltungen, wie z.B. HF-Generatoren, zu einem zeitraubenden Umbau, der Probleme hinsichtlich des elektrischen Kontaktes zwischen den Wellenleiterstücken und des Längenausgleichs aufgrund der veränderten Betriebsfrequenz mit sich bringt und zudem nur eine diskontinuierliche Durchstimmung erlaubt.Therefore, if the operating frequency and / or the impedance ratios change to a greater extent in a tunable HF circuit, it is necessary to replace one transformer inserted in the circuit with another with a different geometry. This leads, especially in power circuits, e.g. HF generators, a time-consuming retrofit, which brings problems with regard to the electrical contact between the waveguide pieces and the length compensation due to the changed operating frequency and also only allows discontinuous tuning.

Es sind daher beispielsweise in der US-A 2 408 745 oder in der DE-C 969 343, variable Anpassungstransformatoren in koaxialer Bauweise vorgeschlagen worden, bei denen innerhalb einer durchgehenden Koaxialleitung mit konstanten Leiterdurchmessern ein in Richtung der Leiterachse verschiebbarer, leitender Hohlzylinder angeordnet ist.Therefore, for example in US-A 2 408 745 or in DE-C 969 343, variable matching transformers in a coaxial construction have been proposed, in which a conductive hollow cylinder which is displaceable in the direction of the conductor axis is arranged within a continuous coaxial line with constant conductor diameters.

Dieser Hohlzylinder bildet zusammen mit den ihn einschliessenden Leiterstücken einen Leitungsabschnitt konstanter Länge und abweichendem Wellenwiderstand. Dieser Leiterabschnitt verbindet zwei an jeder Seite angrenzende Leitungsabschnitte, deren Längensumme konstant ist, und die beide den Wellenwiderstand der zugrundeliegenden Koaxialleitung aufweisen.This hollow cylinder, together with the conductor pieces enclosing it, forms a line section of constant length and deviating wave resistance. This conductor section connects two line sections adjoining on each side, the sum of their lengths being constant, and both of which have the characteristic impedance of the underlying coaxial line.

Durch die Verwendung der gleichförmigen Wellenleitung ergeben sich bei diesem bekannten variablen Anpassungstransformator nur begrenzte Einstellmöglichkeiten.The use of the uniform waveguide results in only limited setting options in this known variable matching transformer.

Es ist andererseits aus der CA-A 853 353 ein differentiell arbeitender Mikrowellen-Phasenschieber bekannt, bei dem zur Einstellung einer variablen Phasenverschiebung zwei Hohlleiterstücke unterschiedlichen Durchmessers durch eine in Richtung der Leiterachse verschiebbare Hohlzylinder-Sektion verbunden werden. Wird diese Hohlzylinder-Sektion verschoben, wird die Phasenverschiebung des einen Hohlleiterstücks verringert, die des anderen dagegen vergrößert, so dass eine differentielle Änderung entsteht. Ein Arbeitsprinzip für einen in weiten Grenzen einstellbaren koaxialen Anpassungstransformator läßt sich aus dem gattungsfremden Gegenstand dieser Patentschrift daher nicht gewinnen.On the other hand, a differentially operating microwave phase shifter is known from CA-A 853 353, in which two waveguide pieces of different diameters are connected by a hollow cylinder section which can be displaced in the direction of the conductor axis in order to set a variable phase shift. If this hollow cylinder section is shifted, the phase shift of one waveguide section is reduced, while that of the other section is increased, so that a differential change occurs. A working principle for a coaxial adaptation transformer that can be set within wide limits cannot therefore be obtained from the non-generic subject matter of this patent specification.

Der vorliegenden Erfindung liegt nun die Aufgabe zugrunde, einen koaxialen HF-Anpassungstransformator zu schaffen, dessen Arbeitsfrequenz und Übertragungsverhältnis in weiten Grenzen kontinuierlich eingestellt werden können, ohne die Einbaumaße des Transformators zu verändern.The present invention has for its object to provide a coaxial RF matching transformer, the working frequency and transmission ratio can be set continuously within wide limits without changing the installation dimensions of the transformer.

Diese Aufgabe wird bei einer gattungsgemäßen Einrichtung durch die kennzeichnenden Merkmale einer der Ansprüche 1, und 4 gelöst.This object is achieved in a generic device by the characterizing features of one of claims 1 and 4.

Gemäß, einem Ausführungsbeispiel besteht der als Koaxialleitung ausgebildete erfindungsgemäße Anpassungstransformator aus einem Außenleiter mit einem konstanten Innendurchmesser und einem Innenleiter mit abgestuften Außendurchmessern, wobei auf dem Innenleiter ein in Richtung der Leiterachse verschiebbarer, leitender Hohlzylinder mit entsprechend abgestuften Durchmessern angebracht und mit dem Innenleiter zumindest hochfrequenzmäßig kurzgeschlossen ist.According to one exemplary embodiment, the matching transformer according to the invention, which is designed as a coaxial line, consists of an outer conductor with a constant inner diameter and an inner conductor with stepped outer diameters, with a conductive hollow cylinder with correspondingly stepped diameters displaceable in the direction of the conductor axis being attached to the inner conductor and short-circuited with the inner conductor at least in terms of radio frequency is.

Der erfindungsgemäße Anpassungstransformator hat den Vorteil, daß seine Arbeitsfrequenz geändert werden kann, ohne die Gesamtlänge des Wellenleiters und damit die Einbaumaße zu ändern. Mit der jeweiligen Arbeitsfrequenz ist gleichzeitig ein bestimmtes Übertragungsverhältnis verknüpft, so daß sich im einstellbaren Arbeitsbereich des Transformators ein kontinuierlicher, kennlinienartiger Zusammenhang zwischen Frequenz und Übertragungsverhältnis ergibt. Diese Kennlinie kann durch geeignete Wahl der geometrischen Parameter so ausgelegt werden, daß sie den Kennlinien anderer HF-Schaltungselemente angepaßt ist. Auf diese Weise läßt sich z.B. ein kontinuierlich abstimmbarer HF-Generator aufbauen, wenn der Impedanzverlauf der verwendeten Senderöhre der Kennlinie des angeschlossenen Transformators entspricht. Weitere Ausführungsbeispiele der Erfindung sind in der Zeichnung dargestellt und werden im folgenden näher erläutert.The matching transformer according to the invention has the advantage that its operating frequency can be changed without changing the overall length of the waveguide and thus the installation dimensions. At the same time, a specific transmission ratio is linked to the respective working frequency, so that there is a continuous, characteristic-like relationship between frequency and transmission ratio in the adjustable working range of the transformer. This characteristic curve can be designed by a suitable choice of the geometric parameters so that it is adapted to the characteristic curves of other RF circuit elements. In this way, e.g. Build a continuously tunable HF generator if the impedance curve of the transmitter tube used corresponds to the characteristic of the connected transformer. Further embodiments of the invention are shown in the drawing and are explained in more detail below.

Es zeigen

  • Fig. 1 das Ersatzschaltbild eines erfindungsgemäßen koaxialen Anpassungstransformators;
  • Fig. 2 ein bevorzugtes Ausführungsbeispiel eines koaxialen Anpassungstransformators;
  • Fig. 3, 4 weitere ausführungsbeispiele eines koaxialen Anpassungstransformators;
  • Fig. 5 Kennlinien eines koaxialen Anpassungstransformators nach Fig. 2;
  • Fig. 6 Kennlinien eines koaxialen Anpassungstransformators nach Fig. 4.
Show it
  • 1 shows the equivalent circuit diagram of a coaxial matching transformer according to the invention;
  • 2 shows a preferred exemplary embodiment of a coaxial matching transformer;
  • 3, 4 further exemplary embodiments of a coaxial matching transformer;
  • 5 characteristic curves of a coaxial matching transformer according to FIG. 2;
  • 6 characteristic curves of a coaxial matching transformer according to FIG. 4.

Das Ersatzschaltbild des erfindungsgsmäßen HF-Anpassungstransformators ist in Fig.1 dargestellt. Ein Wellenleiter W der Länge L ist in mindestens zwei Leiterabschnitte W1 und W2 mit unterschiedlichen Wellenwiderständen Z, und Z2 unterteilt. Die Längen L1 und L2 der Leiterabschnitte sind in einer Weise einstellbar, daß ihre Summe L1 + L2 konstant bleibt, d.h., die erste Länge nimmt um genau den Betrag ab, um den die zweite zunimmt, und umgekehrt. Der Transformator ist im Betrieb durch eine reelle Abschlußimpedanz ZA belastet. Diese Abschlußimpedanz wird in eine reelle Eingangsimpedanz ZE transformiert. Diese Transformation erfolgt, den verschiedenen Leiterabschnitten entsprechend, in mehreren Stufen. Der Leiterabschnitt W2 setzt die reelle Abschlußimpedanz ZA zunächst in eine i.A. komplexe Zwischenimpedanz ZM um, die ihrerseits vom Leiterabschnitt W, in die reelle Eingangsimpedanz ZE transformiert wird. Da die Übertragung in erster Näherung als dämpfungsfrei angenommen werden kann, gehorcht sie der aus der Leitungstheorie bekannten Transformationsgleichung

Figure imgb0001
The equivalent circuit diagram of the RF matching transformer according to the invention is shown in FIG. A waveguide W of length L is divided into at least two conductor sections W 1 and W 2 with different wave resistances Z and Z 2 . The lengths L 1 and L 2 of the conductor sections can be adjusted in such a way that their sum L 1 + L 2 remains constant, ie the first length decreases by exactly the amount by which the second increases, and vice versa. In operation, the transformer is loaded by a real terminating impedance Z A. This terminating impedance is transformed into a real input impedance Z E. This transformation takes place in several stages, according to the different ladder sections. The conductor section W 2 first converts the real terminating impedance Z A into a generally complex intermediate impedance Z M , which in turn is transformed by the conductor section W into the real input impedance Z E. Since the transmission can be assumed to be damping-free in a first approximation, it obeys the transformation equation known from line theory
Figure imgb0001

die die Verknüpfung der Abschlußimpedanz ZA mit der Zwischenimpedanz Zm durch den Leiterabschnitt W2 mit dem Wellenwiderstand Z2 und der Länge L2 beschreibt. Die Größe β ist gleich 2 π/λ mit der Wellenlänge λ im betrachteten Leitungsstück und erfaßt daher den Einfluß der Betriebs- oder Arbeitsfrequenz auf das Transformationsverhalten. Eine analoge Gleichung gilt für den Zusammenhang zwischen ZE, ZM, Z1 und Li. Setzt man den aus der o.a. Gleichung erhaltenen Wert ZM in diese analoge Gleichung ein, ergibt sich aus der Forderung nach einem verschwindenden Imaginärteil von ZE eine Bestimmungsgleichung für diejenigen Wellenlängen, bei denen die Transformation von einem reellen Wert ZA wieder auf einen reellen Wert ZE führt.which describes the connection of the terminating impedance Z A with the intermediate impedance Z m through the conductor section W 2 with the characteristic impedance Z 2 and the length L 2 . The quantity β is equal to 2 π / λ with the wavelength λ in the line section under consideration and therefore detects the influence of the operating or working frequency on the transformation behavior. An analogous equation applies to the relationship between Z E , Z M , Z 1 and Li. If the value Z M obtained from the above equation is inserted into this analog equation, the requirement for a vanishing imaginary part of Z E results in an equation of determination for those wavelengths at which the transformation leads from a real value Z A back to a real value Z E.

Ein einfacher Sonderfall dieser Transformation ist der bekannte zweistufige λ/4-Transformator, der sich dadurch auszeichnet, dass die Argumente β. L der tan-Funktionen den Wert n/2 annehmen und damit zu leicht bestimmbaren Übertragungsverhältnissen führen.A simple special case of this transformation is the well-known two-stage λ / 4 transformer, which is characterized in that the arguments β. L of the tan functions assume the value n / 2 and thus lead to easily determinable transmission ratios.

Ändern sich die Längen L1 und L2 der Leiterabschnitte, ändern sich auch sowohl die Frequenz bei der die Transformation reell ist, als auch das Übertragungsverhältnis. Es ergibt sich ein Kennlinienfeld für den Transformator, das die Arbeitsfrequenz und, bei konstanter Abschlußimpedanz, die Eingangsimpedanz in Abhängigkeit von der Länge eines Leiterabschnitts darstellt. Da die Gesamtlänge L in jedem Fall konstant bleibt, erhält man einen kontinuierlich einstellbaren HF-Anpassungstransformator, dessen Übertragungsverhalten im eingebauten Zustand verändert werden kann.If the lengths L 1 and L 2 of the conductor sections change, both the frequency at which the transformation is real and the transmission ratio also change. The result is a characteristic field for the transformer, which represents the operating frequency and, with a constant terminating impedance, the input impedance as a function of the length of a conductor section. Since the total length L remains constant in any case, a continuously adjustable RF matching transformer is obtained, the transmission behavior of which can be changed in the installed state.

Fig. zeigt ein bevorzugtes Ausführungsbeispiel des erfindungsgemäßen Anpassungstransformators. Als Wellenleiter ist eine Koaxialleitung vorgesehen, die aus einem Außenleiter 1 mit einem konstanten Innendurchmesser D1, sowie einem Innenleiter 2 mit abgestuften Außendurchmessern d1 und d2 besteht. Im Bereich der Durchmesserstufe ist auf dem Innenleiter 2 ein leitender Hohlzylinder 3 angebracht. Der Hohlzylinder 3 ist in Richtung der Leiterachse verschiebbar und im Durchmesser in der gleichen Weise abgestuft, wie der Innenleiter 2. Seine Wanddicke ist vorzugsweise gegenüber den übrigen Abmessungen des Leiters so gering gewählt, daß die Eigenschaften des Innenleiters 2 bezüglich der Wellenausbreitung nur wenig gestört werden. Der Hohlzylinder 3 kann beispielsweise aus dünnem Blech gefertigt und mit einer gut leitenden Schicht überzogen sein. Besonders vorteilhaft hinsichtlich des Gewichts ist es, für den Hohlzylinder aber auch für die anderen Leiter metallisierte Kunststoffe auf der Basis von z.B. glasfaserverstärkten Epoxydharzen zu verwenden. Der Hohlzylinder ist vorzugsweise über Schleifkontakte an seinen Enden mit dem Innenleiter 2 leitend verbunden und bildet so hinsichtlich der Wellenausbreitung in der Koaxialleitung eine verschiebbare Stufe auf dem Innenleiter. Wird der Hohlzylinder 3 z.B. in die in Fig. 1 gestrichelt eingezeichnete Position verschoben, ergeben sich im Transformator Übertragungsverhältnisse, die nicht mehr Leiterabschnitten mit den Längen L1 und L2 entsprechen, sondern Leiterabschnitten mit den neuen Längen L1' und L2', wobei sowohl die Wellenwiderstände Z1 und Z2, als auch die Gesamtlänge L unverändert bleiben.Fig. Shows a preferred embodiment of the matching transformer according to the invention. A coaxial line is provided as the waveguide, which consists of an outer conductor 1 with a constant inner diameter D 1 and an inner conductor 2 with stepped outer diameters d 1 and d 2 . In the area of the diameter step, a conductive hollow cylinder 3 is attached to the inner conductor 2. The hollow cylinder 3 is displaceable in the direction of the conductor axis and graduated in diameter in the same way as the inner conductor 2. Its wall thickness is preferably so small compared to the other dimensions of the conductor that the properties of the inner conductor 2 are only slightly disturbed with respect to the wave propagation . The hollow cylinder 3 can be made of thin sheet metal, for example, and can be coated with a highly conductive layer. It is particularly advantageous in terms of weight to use metallized plastics on the basis of, for example, glass fiber-reinforced epoxy resins for the hollow cylinder but also for the other conductors. The hollow cylinder is preferably conductively connected to the inner conductor 2 at its ends via sliding contacts and thus forms a displaceable step on the inner conductor with regard to the wave propagation in the coaxial line. If the hollow cylinder 3 is moved, for example, to the position shown in dashed lines in FIG. 1, transmission ratios result in the transformer which no longer correspond to conductor sections with the lengths L 1 and L 2 , but with conductor sections with the new lengths L 1 'and L2', whereby Both the wave resistances Z 1 and Z 2 and the total length L remain unchanged.

Die Wellenwiderstände Z1 und Z2 der Leiterabschnitte ergeben sich im übrigen aus den Durchmessern Dl, d, und d2 nach der für die Koaxialleitung bekannten Formel

Figure imgb0002
wobei durch die relative Dielektrizitätskonstante εr der Einfluß eines möglichen Dielektrikums zwischen Außen- und Innenleiter berücksichtigt wird.The wave resistances Z 1 and Z 2 of the conductor sections also result from the diameters D 1 , d, and d 2 according to the formula known for the coaxial line
Figure imgb0002
 whereby the influence of a possible dielectric between the outer and inner conductors is taken into account by the relative dielectric constant ε r .

Um störende Einflüsse auf die Wellenausbreitung im Zwischenraum der Leiteranordnung zu vermeiden, ist es vorteilhaft, die Verschiebung des Hohlzylinders 3 nicht über mechanische Elemente von außen durchzuführen, sondern über eine im Innern des Innenleiters angebrachte Antriebseinheit, die beispielsweise aus einem Elektromotor und einem vorgeschalteten Getriebe bestehen kann, das die Drehbewegung des Motors in eine Schubbewegung in Richtung der Leiterachse umwandelt und über entsprechende Elemente auf den Hohlzylinder 3 überträgt.In order to avoid disruptive influences on the wave propagation in the intermediate space of the conductor arrangement, it is advantageous not to carry out the displacement of the hollow cylinder 3 via mechanical elements from the outside, but via a drive unit fitted inside the inner conductor, which consists, for example, of an electric motor and an upstream transmission can, which converts the rotary movement of the motor into a pushing movement in the direction of the conductor axis and transmits it to the hollow cylinder 3 via corresponding elements.

Ein weiteres Ausführungsbeispiel des erfindungsgemäßen Anpassungstransformators ist in Fig. 3 dargestellt. Der Innenleiter 2 der koaxialen Anordnung ist wiederum mit abgestuften Außendurchmessern d1 und d2 ausgeführt. Der Außenleiter 1 hat ebenfalls abgestufte Innendurchmesser D2 und D3. Der verschiebbare Hohlzylinder 3 ist in seinen Durchmessern dem Außenleiter 1 angepaßt und mit ihm zumindest hochfrequenzmäßig kurzgeschlossen und bildet so einen abgestuften Außenleiter mit verschiebbarer Kante. Daraus resultiert eine Koaxialleitung mit wenigstens drei verschiedenen Leiterabschnitten W1, W2 und W3 mit den entsprechenden Längen L1, L2 und L3 sowie Wellenwiderständen Z1, Z2 und Zg. Da jeder Leiterabschnitt eine Impedanztransformation bedingt, erhält man gegenüber dem in Fig. 2 dargestellten Ausführungsbeispiel einen weiteren Freiheitsgrad für die Realisierung der gewünschten Transformationskennlinien. Darüber hinaus kann der Hohlzylinder 3 ohne Störung der Wellenausbreitung von außen verschoben werden, indem beispielsweise durch einen schmalen Schlitz im Außenleiter 1 ein mit dem Hohlzylinder 3 starr verbundenes Bedienungselement herausgeführt und durch einen außerhalb des Außenleiters 1 angeordneten Antriebsmechanismus betätigt wird.Another embodiment of the matching transformer according to the invention is shown in FIG. 3. The inner conductor 2 of the coaxial arrangement is again designed with stepped outer diameters d 1 and d 2 . The outer conductor 1 also has stepped inner diameters D 2 and D 3 . The diameter of the displaceable hollow cylinder 3 is adapted to the outer conductor 1 and short-circuited with it at least in terms of radio frequency, and thus forms a stepped outer conductor with a displaceable edge. This results in a coaxial line with at least three different conductor sections W 1 , W 2 and W 3 with the corresponding lengths L 1 , L 2 and L 3 as well as characteristic impedances Z 1 , Z 2 and Zg. Since each conductor section requires an impedance transformation, you get compared to that 2 shows a further degree of freedom for the implementation of the desired transformation characteristics. In addition, the hollow cylinder 3 can be displaced from the outside without disturbing the wave propagation, for example by leading out an operating element rigidly connected to the hollow cylinder 3 through a narrow slot in the outer conductor 1 and actuating it by a drive mechanism arranged outside the outer conductor 1.

Ein entsprechender Bedienungsmechanismus kann auch in dem in Fig. 4 dargestellten Ausführungsbeispiel vorgesehen werden, bei dem die Koaxialleitung aus einem Innenleiter 2 mit abgestuften Außendurchmesser d1 und d2 und einem Außenleiter 1 mit konstantem Innendurchmesser D1 zusammengesetzt ist. Der Hohlzylinder 3 ist mit seinem größeren Durchmesser an den Innendurchmesser D1 des Aussenleiters 1 angepaßt und mit einem kleineren Durchmesser D4 versehen, der in seiner Größe zwischen dem Innendurchmesser D1 des Aussenleiters 1 und dem größten Außendurchmesser d1 des Innenleiters liegt. Er ist mit dem Außenleiter zumindest hochfrequenzmäßig kurzgeschlossen und bildet mit ihm zusammen einen Außenleiter mit zwei gleichsinnig verschiebbaren Kanten. Auf diese Weise ist die Koaxialleitung in vier Leiterabschnitte W1, W2, W3 und W4 mit den Längen L1, L2, L3 und L4 und den Wellenwiderständen Z1, Z2, Z3 und Z4 unterteilt. Die Längen der Leiterabschnitte werden durch Verschieben des Hohlzylinders 3 in Abhängigkeit voneinander verändert, wobei die Länge L5 des Hohlzylinders 3 und die Gesamtlänge L der Koaxialleitung konstant bleiben. Der hochfrequenzmäßige Kurzschluß zwischen dem Hohlzylinder 3 und der anliegenden Leiterfläche wird in diesem Ausführungsbeispiel nicht durch Schleifkontakte, sondern durch einen dünnen, dielektrischen Folienbelag 5 vermittelt, der zwischen dem Hohlzylinder 3 und der anliegenden Leiterfläche liegt. Der Folienbelag 5, der z.B. aus Teflon oder Kapton besteht, ermöglicht auf der einen Seite ein nahezu reibungsfreies Gleiten des verschiebbaren Hohlzylinders im Außenleiter 1. Auf der anderen Seite bildet er zusammen mit Hohlzylinder und Außenleiter Koaxialleitungsstücke 6 mit sehr niedriger Impedanz. Dabei ist zu beachten, daß die elektrische Länge der Koaxialleitungsstücke 6 kleiner als 1/4 der ihnen entsprechenden Wellenlänge λG bei der höchsten Betriebsfrequenz ist.A corresponding operating mechanism can also be provided in the exemplary embodiment shown in FIG. 4, in which the coaxial line is composed of an inner conductor 2 with stepped outer diameters d 1 and d 2 and an outer conductor 1 with a constant inner diameter D 1 . The hollow cylinder 3 is adapted with its larger diameter to the inner diameter D 1 of the outer conductor 1 and provided with a smaller diameter D 4 , the size of which lies between the inner diameter D 1 of the outer conductor 1 and the largest outer diameter d 1 of the inner conductor. It is short-circuited to the outer conductor, at least in terms of radio frequency, and together with it forms an outer conductor with two edges which can be displaced in the same direction. In this way, the coaxial line is divided into four conductor sections W 1 , W 2 , W 3 and W 4 with the lengths L 1 , L 2 , L 3 and L 4 and the characteristic impedances Z 1 , Z 2 , Z 3 and Z 4 . The lengths of the conductor sections are changed as a function of one another by displacing the hollow cylinder 3, the length L 5 of the hollow cylinder 3 and the total length L of the coaxial line remaining constant. The high-frequency short circuit between the hollow cylinder 3 and the adjacent conductor surface is not mediated in this exemplary embodiment by sliding contacts, but by a thin, dielectric film covering 5, which lies between the hollow cylinder 3 and the adjacent conductor surface. The film covering 5, which consists for example of Teflon or Kapton, enables on the one hand an almost friction-free sliding of the displaceable hollow cylinder in the outer conductor 1. On the other hand, together with the hollow cylinder and outer conductor, it forms coaxial line pieces 6 with very low impedance. It should be noted that the electrical length of the coaxial line pieces 6 is less than 1/4 of the corresponding wavelength λ G at the highest operating frequency.

In Fig. 5 ist das Kennlinienfeld eines erfindungsgemäßen Anpassungstransformators gemäß dem in Fig. 2 dargestellten Ausführungsbeispiel wiedergegeben. Es zeigt am Beispiel eines Wellenleiters mit der Gesamtlänge L = 1 m, den Wellenwiderständen Z1 = 30Q und Z2 = 75 Ω und der Abschlußimpedanz ZA = 50 Q die Verläufe der Betriebefrequenz f (in MHz) und der aus der Transformation resultierenden Eingangsimpedanz ZE (in Q) in Abhängigkeit von der Länge L2 (in m). Man erkennt, daß über den gesamten Variationsbereich der Länge L2 keine einheitliche, eindeutige Lösungskennlinie existiert, sondern eine Vielfalt von Kennlinien der Frequenz (fi ... f6) und der Eingangsimpedanz (R1 ... R6) für bestimmte Längenbereiche. So ist beispielsweise aus dem zusammengehörenden Kennlinienpaar f2 und R2 zu entnehmen, daß bei einer Länge L2 zwischen 0 und 0,4 m die Betriebsfrequenz gemäß Kurve f2 zwischen 150 und 240 MHz monoton variiert, während gemäß Kurve R2 die Eingangsimpedanz ZE d.h., die durch den Anpassungstransformator transformierte Abschlußimpedanz ZA, zwischen 50 und 113 Ω variiert, mit einem ausgeprägten Maximum bei L2 = 0,33 m.FIG. 5 shows the characteristic field of an adaptation transformer according to the invention in accordance with the exemplary embodiment shown in FIG. 2. Using the example of a waveguide with the total length L = 1 m, the wave resistances Z 1 = 30Q and Z 2 = 75 Ω and the terminating impedance Z A = 50 Q, it shows the curves of the operating frequency f (in MHz) and the input impedance resulting from the transformation Z E (in Q) depending on the length L 2 (in m). It can be seen that there is no uniform, unambiguous solution characteristic over the entire range of length L 2 , but a variety of characteristics of frequency (fi ... f 6 ) and input impedance (R 1 ... R6) for certain length ranges. For example, it can be seen from the pair of characteristic curves f 2 and R 2 that the operating frequency according to curve f 2 varies monotonically between 150 and 240 MHz with a length L 2 between 0 and 0.4 m, while according to curve R 2 the input impedance Z E ie, the terminating impedance Z A , transformed by the matching transformer, varies between 50 and 113 Ω, with a pronounced maximum at L 2 = 0.33 m.

Von besonderer Bedeutung für die Anwendung ist das Kennlinienpaar R3, f3. Es zeigt dass der erfindungsgemäße Anpassungstransformator sich bei nur geringer Änderung des Transformationsverhältnisses durch Änderung der Länge L2 über einen grossen Frequenzbereich von über 150 MHz kontinuierlich abstimmen lässt.The pair of characteristics R 3 , f 3 is of particular importance for the application. It shows that the adaptation transformer according to the invention can be continuously tuned over a large frequency range of over 150 MHz with only a slight change in the transformation ratio by changing the length L 2 .

Entsprechende Kennlinienfelder beschreiben auch das Betriebsverhalten der Ausführungsbeispiele gemäß den Fig. 3 und 4. So ergibt sich für eine Anordnung gemäß Fig. 4 der in Fig. dargestellte Kennlinienverlauf. Dabei gehört das Kurvenpaar R1, f1 zu einer Ausführung mit den Abmessungen L1 + L2 = L3 + L4 = L5 = 1,5 m und den Impedanzen Z1 = Z3 = 30 Q, Z2 = 10 2 und Z4 = ZA = 50 Ω. Für das Kurvenpaar R2, f2 gelten bei unveränderten Impedanzen die entsprechenden Abmessungen L1 + L2 = 1,25 m und L3 + L4 = L5 = 1,75 m.Corresponding characteristic curve fields also describe the operating behavior of the exemplary embodiments according to FIGS. 3 and 4. Thus, the characteristic curve shown in FIG. 4 results for an arrangement according to FIG. 4. The pair of curves R 1 , f 1 belongs to a version with the dimensions L 1 + L 2 = L 3 + L 4 = L 5 = 1.5 m and the impedances Z 1 = Z 3 = 30 Q, Z 2 = 10 2 and Z 4 = ZA = 50 Ω. The corresponding dimensions L 1 + L 2 = 1.25 m and L 3 + L 4 = L 5 = 1.75 m apply to the pair of curves R 2 , f 2 with unchanged impedances.

Insgesamt lassen sich nach der Erfindung durch geeignete Wahl der geometrischen und elektrischen Parameter sowie durch Kombination mehrerer beweglicher und fester Durchmesserstufen an Außen- und/oder Innenleiter Anpassungstransformatoren aufbauen, deren Kennlinien dem jeweiligen Verwendungszweck in einer HF-Schaltung optimal entsprechen, und deren Kenngrößen Betriebsfrequenz und Übertragungsverhältnis in weiten Bereichen kontinuierlich verändert werden können, ohne daß ein Aus- und Einbau des Transformators selbst erforderlich ist.Overall, matching transformers can be constructed according to the invention by suitable selection of the geometric and electrical parameters as well as by combination of several movable and fixed diameter stages on outer and / or inner conductors, the characteristics of which optimally correspond to the respective intended use in an HF circuit, and the characteristics of operating frequency and Transmission ratio can be changed continuously over a wide range without the need to remove and install the transformer itself.

Claims (8)

1. RF matching transformer in the form of a coaxial line having a fixed length (L), this coaxial line consisting of an outer conductor (1) and an inner conductor (2) and being subdivided into a plurality of conductor sections which have in each case a particular length and a particular characteristic impedence, and in which arrangement, between the outer conductor (1) and the inner conductor (2), a conductive hollow cylinder (3) is coaxially arranged which is displaceable in the direction of the conductor axis and which is conductively connected to the inner conductor (2) at least with respect to radio frequencies, characterized in that
a) the inner conductor (2) is provided with a step in diameters generated by two different outside diameters (d" d2) of the inner conductor (2);
b) the hollow cylinder (3) is applied resting against the inner conductor with a diameter step corresponding to the diameter step of the inner conductor (2), in such a manner that the diameter step of the inner conductor (2) is replaced by the displaceable diameter step of the hollow cylinder (3) with respect to wave propagation; and
c) the hollow cylinder (3) determines with its diameter step two adjacent conductor sections (W1, W2) having a different characteristic impedence (Z1, Z2), the lengths (Ll, L2 and L'l, L'2) of which sections are adjustable in such a manner that their sum remains constant (Figure 1, 2).
2. RF matching transformer in the form of a coaxial line having a fixed length (L), this coaxial line consisting of an outer conductor (1) and an inner conductor (2) and being subdivided into a plurality of conductor sections which have in each case a particular length and a particular characteristic impedence, and in which arrangement, between the outer conductor (1) and the inner conductor (2), a conductive hollow cylinder (3) is coaxially arranged which can be displaced in the direction of the conductor axis and which is conductively connected to the outer conductor (1) at least with respect to radio frequencies, characterized in that
a) the outer conductor (1) is provided with a diameter step generated by two different inner diameters (D2, D3) of the outer conductor (1),
b) the hollow cylinder (3) is arranged resting against the outer conductor with a diameter step corresponding to the diameter step of the outer conductor (1), in such a manner that the diameter step of the outer conductor (1) is replaced by the adjustable diameter step of the hollow cylinder (3) with respect to wave propagation; and
c) the hollow cylinder (3) determines with its diameter step two adjacent conductor sections (W1, W2 + W3) having a different characteristic impedence, the lengths (L1, L2 + L3) of which sections are adjustable in such a manner that their sum remains constant (Figure 3).
3. RF matching transformer according to Claim 2,
characterized in that
a) the inner conductor (2) also has a diameter step generated by two different outside diameters (d1, d2) of the inner conductor (2); and
b) the diameter step of the inner conductor (2) is arranged in that section of the line in which the diameter step of the hollow cylinder (3) can be displaced (Figure 3).
4. RF matching transformer in the form of a coaxial line having a fixed length (L), this coaxial line consisting of an outer conductor (1) and an inner conductor (2) and being subdivided into a plurality of conductor sections which have in each case a particular length and a particular characteristic impedence and in which arrangement, between the outer conductor (1) and the inner conductor (2), a conductive hollow cylinder (3) is coaxially arranged which can be displaced in the direction of the conductor axis and which is conductively connected to the outer conductor (1), at least with respect to radio frequencies, characterized in that
a) the inner conductor (2) is provided with a diameter step generated by two different outer diameters (di, d2) of the inner conductor (2);
b) the outer conductor (1) has a constant inner diameter (D,);
c) the hollow cylinder (3) is arranged resting against the outer conductor (1), has a constant length (L5), an outer diameter equal to the inner diameter (D,) of the outer conductor (1) and an inner diameter (D4) which is greater than the outer diameters (di, d2) of the inner conductor (2), in such a manner that an outer conductor having two edges which are displaceable in the same direction is formed by the hollow cylinder (3); and
d) the diameter step of the inner conductor (2) is arranged with respect to the displaceable hollow cylinder (3) in such a manner that it is always located between the two edges which can be displaced in the same direction (Figure 4).
5. RF matching transformer according to one of Claims 1, 2, 3 and 4, characterized in that the conductors (1, 2) and/or the hollow cylinder (3) consist of a metallized plastic.
6. RF matching transformer according to one of Claims 1, 2, 3 and 4, characterized in that the hollow cylinder (3) is conductively connected via a sliding contact (4) to the conductor surface resting against it.
7. RF matching transformer according to one of Claims 1, 2, 3 and 4, characterized in that the hollow cylinder (3) is short-circuited with respect to radio frequencies via a dielectric foil coating (5) to the conductor surface resting against it.
8. RF matching transformer according to Claim 1, characterized in that the hollow cylinder (3) is connected to a drive unit arranged in the inner conductor (2).
EP83710019A 1982-06-04 1983-04-11 Hf adaptation transformer Expired EP0097112B1 (en)

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Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5545949A (en) * 1994-07-29 1996-08-13 Litton Industries, Inc. Coaxial transmissioin line input transformer having externally variable eccentricity and position
US7604633B2 (en) 1996-04-12 2009-10-20 Cytyc Corporation Moisture transport system for contact electrocoagulation
US6508815B1 (en) * 1998-05-08 2003-01-21 Novacept Radio-frequency generator for powering an ablation device
US8551082B2 (en) 1998-05-08 2013-10-08 Cytyc Surgical Products Radio-frequency generator for powering an ablation device
US6664881B1 (en) 1999-11-30 2003-12-16 Ameritherm, Inc. Efficient, low leakage inductance, multi-tap, RF transformer and method of making same
US8486060B2 (en) 2006-09-18 2013-07-16 Cytyc Corporation Power ramping during RF ablation
US8558637B2 (en) * 2010-05-12 2013-10-15 Mediatek Inc. Circuit device with signal line transition element

Family Cites Families (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR958201A (en) * 1950-03-06
US1927393A (en) * 1931-07-10 1933-09-19 Int Communications Lab Inc Transmission system for ultrashort waves
US1928408A (en) * 1931-11-24 1933-09-26 Int Communications Lab Inc Shield for leads from micro-ray tubes
US2408745A (en) * 1941-11-11 1946-10-08 Gen Electric Co Ltd Variable impedance transformer
DE945261C (en) * 1942-03-11 1956-07-05 Elektronik Ges Mit Beschraenkt Device for adjusting the phase position of an electromagnetic oscillation in a waveguide
CH233273A (en) * 1942-05-12 1944-07-15 Telefunken Gmbh High frequency line.
US2463415A (en) * 1943-08-26 1949-03-01 Westinghouse Electric Corp Shorting bar for concentric lines
DE969343C (en) * 1943-12-25 1958-05-22 Funkstrahl Ges Fuer Nachrichte Arrangement for the adjustable adaptation of a frequency-dependent terminating resistor of an ultra-high frequency power line to the characteristic impedance of the same
BE489277A (en) * 1948-06-16
US2900610A (en) * 1955-05-19 1959-08-18 Richard W Allen Variable impedance transformer
CA853353A (en) * 1967-12-27 1970-10-06 Her Majesty The Queen In Right Of Canada As Represented By The Minister Of National Defence Of Her Majesty's Canadian Government Differential microwave phase shifter

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
H. Meinke, F. W. Gundlach "Taschenbuch der Hochfreuenztechnik", Springer Verlag, Berlin, 3 Auflage, 1968, Seiten 384-385 *

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