DE1491530A1 - Electron discharge device - Google Patents

Description

VABIAN ASSOCIATES

Palo Alto / California
Y. St.v.Aaerika

Electron discharge device

Priority * July 23, 1964 - V. St. ν. America - Ser. STo. 384.668

The invention relates generally to radio frequency electron discharge devices and in particular those devices with delay lines Tom type Hing and Stab derived from the helix These high frequency electron discharge devices are particularly useful in frequency generators, broadband high power amplifiers, etc. useful. A spiral-derived delay line of the Hing and Stange type as shown in U.S. Patent 2,937,311. is an excellent vehicle to reproduce reasonably high Performances of an electromagnetic traveling wave for interaction with electron beams and the following amplification »The thermal Capacity of this special line type, as it is for example in U.S. Patent 2,853,642 is considerably increased Dimensions by using stub beams for the delay line improved according to this publication. Usually the length of the bearing stumps is a quarter of a wavelength, determined at the middle of the line's operational passband * If

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However, the Yervended beam powers become laxer and higher, the stability of tubes with such lines becomes the most important

Factor that influences the load capacity of such tubes

Higher order management modes become more difficult to stabilize internally and can seriously affect operational behavior, when the power increases · For example, a limit thawing on the delay line by lifting electric fields Tension caused by the building up of tone resonance modes and corresponding inergy losses to these modes, the energy available for the foundation leo due to the fact that the usable tube operating power level is limited or the tube is destroyed · Bine Delay line and associated traveling wave tube can be seriously limited if stabilization techniques are not used, as soon as power levels of several kilowatts are reached

Some higher-order circular modes, such as the ring mode and the stump mode, occur as disturbing vibration modes. One way of suppressing these resonant circuit ohms is to use stub lengths that decrease in the direction of the tube axis. (Sohwingungsstartstrox) increased for the stump mode and obtained a significantly increased stabilization of a pulse amplifier with such a reduction mechanism. The stump mode can be defined as a higher-order resonance conduction mode, in which the length of the supporting stumps determines the upper limit frequency of the mode.According to the definition, the fundamental mode or the lowest order propagation mode for any periodic delay line is characterized by a certain field distribution in a plane perpendicular to the direction of propagation, and this field distribution is independent of the position of the propagation axis · Fortpflanzungemodi along a higher order, such as the Stumpf mode, are defined herein as propagation modes in contrast to the fundamental mode, which also duroh yn a special field image of a plane transversely in the Fortpßanzungsrichtung}

he field image is individually different and different also from other modes

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Once the situation has elapsed, another solution to the problem will be available geaaoht, eiae Hoohleiatungs traveling wave tube ait one τοη the Wendelleitvae derived Yersögerungsleitung, a Yersögerungsleituag το »Type Hing« ad rod, which is kept old footsteps », Buren an iaa single going measurement of the high frequency Durohlass ·· band of an old stump-fit pipe tob type Hing and Stange and an analysis of the Böhrenhetrieb data has been established been, the · the length of the stage «in beatiaaender factor in the stabilization of a tone Stttapfen geattttxten Hing- und Stange-TertOgerunga · management is. You just mentioned reduction of the length of the arm someaaaaen adäauat, ao that aiae Hoehleistungsa-Vanderfeldröhre Stabilized with a tt »n Stüapfen Gestütstea TeraOgerungsleitung becomes · if an aolohe tube but above the operating band stubborn Saturation, results in a reduction in output power in the middle of the operating band. Saduroh is worshiped that the reduction technique does not represent the exact Optiaua in addition to a great constant stabilization of the Stuapfaodus.

The invention provides a solution to this problem of a depressed Sättiguagaauagangaleiatuag reravailable, which at dea above-mentioned shrinking treadmill due to deviation of the usual length of the sleeve 1/4 ^, which in all known Stuapfgestütsten ring and rod cables is used · piping Nearly upward or downward deviation from the usual stage length of a quarter of a wavelength is combined with the Improved stability properties will be described in more detail later, here it should only be said that there is a deviation below, both with regard to the bandwidth and the manufacturing costs is preferred · Inventionageaäaa it was found that with a Step length of about i / 6 \ at f (center frequency of the operating band), the step mode is sufficiently raised in frequency can be, among other things, an interaction of a »wide Haraonisohen der Signal frequency ait dea beam xa, through which otherwise-

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Butt-modulus oscillations can be attached. Through the Brf indang a careful range τοη 8tumpflängen is also taught, namely 1 / 16Λ ₀ to 3 / 16A ₀ and 5 / ΐ6λ _ο * i »V3Ä _e » «** ** 41« ·· »B # - rows are the useful 8ttuipf parameters for stabilization ·

Furthermore, through the discovery, in relation to stump support, "wipe." which are inductive and / or capacitive disturbances, taught that Deviations τοη 1 / 4A ι expressed in the wavelength in free Out, can be very clearly and a plane electromagnetic Wave, which through the disturbed area speed, which differs τοη the speed of light, also falls within the scope of the invention and see τβη of the conventional teaching of a quarter wavelength differentiates, the Blunt mode is suppressed when the expressions are chosen as follows will be

The stumps "olle" in their length measurements in the following sizes fall «

1/16 Λ <CL <C 3/16 Λ «ad 5 / ΐδλ ^ L <C1 / 3X

where L is the stump length, i.e. the physical length of the path along the surface of the stump », measured Tem EmAe of the stump on the outside diameter of the hingleitung on the stump base or root, and Λ "e / f, with f the center frequency of the Durehlassbandea the butt-studded line and ο the speed of a flat electromagnetic wave in the dielectric medium or in th dielectric media between the stumps, averaged over the Length L of the stump

The main aim of the invention is therefore to develop a new type of Tersögeruags " Line and a better high-frequency-Ilektronen-Sntloadseiariohtuag to make available.

The essential feature of the invention is that a delay line derived from the helical line is made available with a new type of support element.

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Veiter becomes through the invention of a τοη the helical line derived delay line Tom type ring and rod »it stump» Carrying sound approx. 1 / 6A available, measured in the middle of the line's operating frequency band.

Veiter is using a butt-supported, τοη the helical line derived delay line tob type ring and rod Availably mowed, where the length of the legs is within the following Grensen is lying down

/ ^ and

where L is the butt length and \ is determined at f (the center frequency of the line operating band).

Veiter becomes duroh the invention a butt-studded, τοη the helix Derived delay line tob type ring and rod Teravailable maoht, with the length of the stumps within the following Grensen lies

1 / 16Λ <L «£ - 3 / i6> \ and 5/1 ⁶ λ ^. L ^ L i / 3 / \

where L is the step length, i.e. the physical length of the path along the surface of the stump, sat to the end of the stump on the outer diameter of the ring line on the stump base or "root, and Λ "o / f t where f is the center frequency of the Surohlassband of the most blunt line and ο the speed of a flat line electromagnetic wave in the dielectric medium or in the dielectric media swisohen the stumps is averaged over the Length L of the stump.

Furthermore, according to the invention, such a delay line is shown in FIG The above is used in a high frequency sheet electron discharge device, in the one with electromagnetic traveling field effect is being worked

These and other features of the invention will become apparent from the following description in conjunction with the drawing} it seigern

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Fig. 1 is a partially cut side view of an invention

according to traveling wave tube;

2 shows a section along the line 2-2 in FIG 3 is a diagram of the delay line shown in FIG. 1

and 2 for visualization Figure 4 is a graphical representation of peak output power depending on the * frequency of a delay line » as shown in FIGS. 1 and 2 is shown, but »it is butt 1 an ge η τοη V ^ Ao ' ¹ ^ ¹ *

5 graphically shows the dependency of the center outlet line τοη the frequency in a delay line that is ine Traveling wave tube naoh Fign. 1 and 2 is installed and in which the Stabilisierungsteehnlk according to the invention is applied is.

In Fig. 1 is a traveling wave tube 7 «with an electron syringe 8, a conductive body 9 »a collector 10, an anode 11, a Sound of the helical line derived delay line 12 τοη type Ring and rod, which have a number of τοη weohsel effect columns 13 wischen rings 14 arranged at a distance from one another are defined, Support stumps 15 and RF input and output couplers 16 and 17, respectively. The traveling wave tube shown in Fig. 1 is axially aligned with a center axis of propagation Z. Sin electron beam 18, which proceeds from the electron syringe part 8, as shown by broken lines, runs along the central axis to the collector 10. Because the interaction between an electron beam and RF energy on delay lines is known, no further one is available Explanation required for reinforcement purposes. A common line separator 19 is between the parts of the delay line arranged, and the lines are with two loss loads 20, 21 completed to absorb unwanted RF energy in a known manner. Preferably, the conductive body 9 ″ is two Cooling channels 22, 23 {Fig. 2) in order to improve the heat dissipation and thus the resilience of the line. Usual load

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wülate 24, 15 are provided for sweakaaaaigerweiae, ta «in wider ones • and sm are preserved, and the stumps are reduced in size, including the variability of the Kreiaea plane, like the circular properties, see below verbeaaera

la Pig · 3 i · * aimCJ «^ J -Diagraaa of the Durohlassband the line naoh Fig. 1 dargeatel.lt · T - β iat a curve for the Liohtgeoh Speed, while ▼ - u _o the character! at Ik for the operations« 8trahlapension or 8tr & hl speed iet. The old fundaaentalaedua is the operating line of the pipe with a well-bagged king and rod pipe from Pign. 1 and 2 Dia-triangular can line k shows the resulting characteristic line daa pundaentalaodua, if a kuraer step τοη about 1/6 \ is usedDia can line B shows the pounding of the fundaaental- ■ odua, when a large or longer carrying step is used, for example 5/16 \ · The interrupted can line k * gives the characteristic curve daa aloh resulting 8tuapfnodus, if a course 8tu * pf of about l / i \ is used ^ from which aioh results that the 8tuapfsiodua u nioht atBrt · Dia interrupted characteristic curve B * seigt the aioh resulting Stuapfnodus characteristic curve, if a Stuirpflange of about 5 / ΐ · Λ _β is used, ea results from aioh that the

StuapfBodua occurs far above 2? ^ F, but from u lasier

ο ο

nooh is disturbed, aa aaoh alao still gives a possibility for an 8twapfaodua-Veohseling effect, if there is not any other suitable device sur 3ohwang "uBterdrttOlnmg w -w -w -w -w -wt" the characteristic line removed from 8tuapfaodua shows a mode which, like through the can line, is clearly visible and has a very low group swiftness, so that the heaonan ·· »conductionaaigaaaohhaften are shown · Ersiohtlieh causes a length of 1/4 X, beatlaat at f _Q , Btuapfaodusaohworbenzen with wide haraoniae, as indicated by the intersection of u _Q and the Stuapfaodaak characteristic curve becomes (see Fig. 3) ·

If a stage length of 1 / 6A ₀ is used, the stage mode is raised enough in terms of frequency, including a synohrene

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To prevent interaction with the operating jet speed, as shown by the curve labeled "stump mode, short stumps". A consideration of the fundamental mode characteristics A and B shows their interference or deviation from the fundamental modulus for stump lengths of a quarter wavelength A stump of _{1/6 A or} because this is somewhat less scattering, compared with the characteristic curve for a quarter wavelength, gives advantageous results in terms of the operating bandwidth of the tube as well as in terms of stabilizing a traveling field section with the short stump technique shown here.

The in FIGS. 1 and 2, when using the following parameters * butt length * 1/6 / \, outer ring radius - 0.075 Λ ₀ »truncated vertex angle - 22.5 ° t waveguide height about 1/4} \ , distance between loading bead and outer ring radius of 0.025 Λ »and when used in conjunction with a tube that has a saturation gain of 30 dB over a bandwidth of 167ε, a beam speed of about 36 kV and I4 amps of beam current, the saturation RF output characteristic curve according to FIGS. 4 and 5, the characteristic curve according to FIG. 4 being obtained without the stump length regulation according to the invention for stabilization. 4 shows the usual saturation output characteristic, for a stump length of ΙΑ \ »even with a decreasing stump length for stabilization, and it can be seen that at f there is a considerable drop in the output

gangs Ie istung If a stump length of I / 6 Λ is used, it can be seen that the lowering of the output power characteristic at f does not apply. When comparing FIGS. 4 and 5, it can be seen that neither the bandwidth nor the peak output power is reduced. The stump length of i / o Λ at f is a preferred stump dimension, but the invention is not limited to this. It was found that the following stump dimensions can be used advantageously in terms of length in order to achieve a stump mode ohmic oscillation in high-performance traveling wave tube sections with butt-shaped

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supported ring · * and rod delay lines, namely butt lengths within the following limits: 1/16 y \ ₀ ^ L «ü3 / i6 / \ _o and 5/16 / \ ^ :. L ^ .1 / 5 / \ _Q

where L is the length of the stump in a plane transverse to the Z-axis and A is determined at the center frequency f of the frequency band that is to be propagated along the line.

It should be mentioned that the short stumps (<<. I / 4 λ) are preferred because they easily have every possibility for a correspondence between signal energy within the operating band and frequencies, where the stump mode is propagated should be avoided, including second harmonic of any frequency within the operating band. Furthermore, the characteristic curve u does not intersect the

Short stump characteristic, so that it is ensured that the stump mode is not fueled by noise.

The greater butt length (7 ^ 5/16 Λ) easily avoids any correspondence between the signal energy at frequencies within the operating band as well as at second harmonics of any frequency within the operating band with frequencies at which the butt mode propagates (Λ / 2) but ensures not a complete stabilization because excitation by noise of the beam is still possible, as indicated by the intersection of the characteristic u and the stump mode for long stumps B ¹ .

Precisely the avoidance of stump mode oscillations through second Harmonics of frequencies within the operating band, however, result in a substantial improvement for the hearing designer, entirely considered by itself alone.

As already mentioned, inductive and / or capacitive interference between the stumps the deviation from one

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i / 4 λ, expressed in wavelengths in free space, very strongly emphasized be, it also falls within the scope of the invention a plane electromagnetic wave that is in the disturbed area with any Runs at a speed different from the speed of light, and in this case the length measurement according to the invention to achieve stump mode suppression expressed as follows:

The stumps have a length dimension in the following ranges lies:

/ \ and 5/16 ^ <c L «CJ / 3 / \

where L is the stump length, i.e. the physical length of the path along the surface of the stump, measured from the end of the stump at the outer diameter of the ring line to the stump base or root, and / \ - c / f, where f is the center frequency of the passband of the stump-supported line and c is the velocity of a plane electromagnetic wave in the dielectric medium or in the dielectric media between the stumps, averaged over the length of the stump L.

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Claims (1)

H91530 M. V1 P65 D Claims 1 · High frequency electron discharge device for propagation electromagnetic energy within a frequency band, with a delay line made up of a number of spaced apart conductive rings which are passed through conductive Stumps are connected to one another, characterized in that the length of the stumps at the center frequency f of the operating band a is chosen so that there is no correspondence between frequencies within the operating band and their second harmonics on the one hand and frequencies at which the stumps have I / 2 A, where ^ is the wavelength in the open Space is. 2. Device according to claim 1, characterized in that the physical length L of the stumps is optionally within the following limits 1/16 / \ _O ^ LZ.5 / 16A _O / \ _o where A is ^the wavelength in free space at frequency f. 3. Device according to claim 2, characterized in that the physical length L of the stumps is approximately 1/6 A ₀ . 4 * device according to claim 1, characterized in that the physical length L of the stumps along the stump surface, measured from the outside diameter of the ring main to the stump base or root is optionally within the following limits - A2 - 909841/0575 At 1/16 A ^ K3 / 16 A
5/16 / \ ^ L < where Λ * c / f with o = average speed of a plane electromagnetic wave in the dielectric medium or the dielectric media between the stumps, averaged over the Length of the stumps. 5 »Device according to one of claims 1-4, characterized in that that the delay line is derived from a helical line, in particular a line of the ring and rod type. 6. Device naoh one of claims 1 - 51, characterized in that that the longitudinal axis of the stumps is transverse to the longitudinal axis of the device. 909841/0575 OFBGINAi. JNSPECTED