US2654047A - Beam traveling wave amplifier tube - Google Patents

Beam traveling wave amplifier tube Download PDF

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Publication number
US2654047A
US2654047A US3325A US332548A US2654047A US 2654047 A US2654047 A US 2654047A US 3325 A US3325 A US 3325A US 332548 A US332548 A US 332548A US 2654047 A US2654047 A US 2654047A
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United States
Prior art keywords
transmission line
wave
beam path
conductors
collector electrode
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US3325A
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English (en)
Inventor
Clavier Andre Gabriel
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International Standard Electric Corp
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International Standard Electric Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority to BE486897D priority Critical patent/BE486897A/xx
Application filed by International Standard Electric Corp filed Critical International Standard Electric Corp
Priority to US3325A priority patent/US2654047A/en
Priority to GB26285/48A priority patent/GB675187A/en
Priority to FR979203D priority patent/FR979203A/fr
Application granted granted Critical
Publication of US2654047A publication Critical patent/US2654047A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J25/00—Transit-time tubes, e.g. klystrons, travelling-wave tubes, magnetrons
    • H01J25/34—Travelling-wave tubes; Tubes in which a travelling wave is simulated at spaced gaps
    • H01J25/36—Tubes in which an electron stream interacts with a wave travelling along a delay line or equivalent sequence of impedance elements, and without magnet system producing an H-field crossing the E-field
    • H01J25/38—Tubes in which an electron stream interacts with a wave travelling along a delay line or equivalent sequence of impedance elements, and without magnet system producing an H-field crossing the E-field the forward travelling wave being utilised

Definitions

  • the present invention relates to travelling wave amplifiers and more particularly to travelling wave amplifiers with a large amplification factor and with large power output.
  • travelling wave amplifiers utilize reduced-velocity-wave guides for propagation of an electromagnetic wave with a longitudinal electric field component along an electron beam path.
  • Such a tube is limited in power output.
  • the most common type of reduced-velocity-wave guide which can be excited in a mode with a longitudinal electric field component is one made from a helix of wire and a travelling wave amplifier tube using a helix is limited in power output fundamentally because of the size of the helix. This limits the size of the beam current and hence the kinetic energy of the beam which is equal to the product of the beam current and the beam voltage and which is directly proportional to the power output of the tube. Also the length of helix is limited and hence the amplification.
  • the transmission line may also be built much larger than the reducedvelocity-wave guide and hence the beam current may be made larger and more power output may be obtained.
  • FIG. 1 An envelope l encloses an electron gun 2, a focusing and accelerating electrode 3, and a collector electrode 4 defining a beam path therebetween.
  • a coaxial transmission line comprising an outer conductor 5 and a tubular inner conductor 6 is arranged with the inner conductor coaxially about the beam path.
  • a is the attenuation constant
  • B is the phase constant
  • e is an arbitrarily small constant
  • Equation 4 The positive sign in Equation 4 corresponds to forward waves.
  • Equation 3 When this expression for the propagation constant is substituted in Equation 3, three solutions are obtained for a and e. Equation 3 can be written approximately as follows:
  • Equation 5 Setting the rational and irrational parts of Equation 5 equal to zero two equations 101' e and. 1
  • E63 has a phase velocity smaller than the electron velocity and is amplified.
  • Equation 5c' The amplification factor a for the foreward wave of Equation 5c'is as follows:
  • I0 is the current of the electron beam directed coaxially through the inner coaxial conductor 6 of the transmission line
  • Z0 is the characteristic impedance of the line
  • )t the wavelength along the transmission line
  • the transmission line may be constructed so that the expression is a-maximum.
  • An expression for may be obtained in terms of the radii of the inner and outer conductors a and b of the transmission line and this is as follows for the case in which the phase velocity on for the electromagnetic wave propagated along the line is close to the steady component of the electron velocity.
  • the construction and operation of the tubes of Figs. 1 and 3 are as follows.
  • the electron gun 2 is indirectly heated by a coil 9, leads Iii and I I of said coil being connected across a small portion of a voltage source I2.
  • the electron gun 2 is connected directly to lead I0, lead I being connected to the negative side of the high tension voltage source I2.
  • a lead I3 from the focusing and accelerating electrode 3 is connected to the positive side of the source I2.
  • a lead I 4 from the collector electrode 4 is connected to a low voltage point of said source I2 so that the unconverted portion of the kinetic energy of the beam does not necessarily appear as dissipated power at the collector electrode.
  • a lead I5 from the inner conductor is connected to the positive end of the high tension source I2.
  • the velocity of the wave propagated down the transmission line is retarded by a material I of high dielectric constant placed between the conductors 5 and 6.
  • a material I of high dielectric constant placed between the conductors 5 and 6.
  • This may conveniently be the same material as that of the envelope I of the device and in this case it is formed integrally therewith, the envelope I being shaped to fit closely between the conductors 5 and 5.
  • the transmission line 5, 6 in Fig. 1 and 6, 8 in Fig. 2 is connected to transverse coaxial conductors I53, I! and I8, IS, the inner conductors I6 and I8 being sealed through the envelope 2.
  • Quarter wave length short circuited coaxial lines 20 and 2I are arranged for matching the impedances of lines I6, I! and I8, I9 to that 6 of lines 5, G in Fig. 1 and 6, B in Fig. 2.
  • quarter wave length open lines 22 and 23 are arranged to prevent radiation from the ends of the line.
  • a wave is propagated down the transmission line from the end adjacent the electron gun 2 to the end adjacent the collector electrode 4 at a velocity slightly less than the velocity no of the electrons in the beam.
  • the inner conductor 6 of both structures of Figs. 1 and 2 is constructed of parallel wires and inside this conductor there occurs a component of the electric field of the wave parallel to the beam current path.
  • the wave and the beam interact in a manner similar to the interaction that occurs in an ordinary travelling wave amplifier tube in which the wave is propagated along the beam path through a slowed-up wave guide.
  • the wave is amplified.
  • a solenoid 24 is provided around the tube in both cases for focusing the beam through the inner conductor 6.
  • FIG. 4 A third embodiment of my invention is shown in Fig. 4.
  • the beam is pro- J'ected along a. transmission line 25, 26 outside of the outer conductor thereof.
  • a cylindrical gun 21 is arranged outside of and coaxially surrounding conductor 26 and a cylindrical focusing electrode 28 is arranged coaxially around the gun 21.
  • a collector electrode 29 is arranged at the end of the beam path coaxially about the transmission line and between the accelerating and the collecting electrodes 28 and 29 there is arranged a metal cylinder 30 coaxially about the transmission line 25, 26 for shielding the envelope I from the beam.
  • the outer conductor 26 of transmission line 25, 26 is composed of a plurality of parallel wires and thus mutual inductive coupling M between the wave propagated down the transmission line and the beam is obtained.
  • the inner conductor 26 is a plain solid conductor.
  • the transmission line 25, 26 is extended through the envelope I of the tube at both ends and thus there are provided means for connecting input and output transmission lines.
  • the wave propagated down the transmission line is slowed up by placing a material 3
  • the squirrel cage-type of conductor is one form only which will give a large mutual inductive coupling between the wave propagated down the transmission line and the beam focused along the line outside the space between the conductors of the line.
  • Other constructions will occur to those skilled in the art.
  • other means for reducing the velocity of the wave propagated down the transmission line may be used. While I have described my invention with reference to a particular embodiment, it is not intended to be limited thereto, but only as defined in the appended claims.
  • a travelling wave amplifier tube comprising an electron gun and a collector electrode defining a beam path therebetween, a transmission line including two conductors arranged adjacent to and along said beam path for propagating an electromagnetic wave along said beam path in the direction from said gun to said collector electrode, the space between said conductors being separated from said beam path by one of said conductors, said one conductor being subdivided and aesaou disposed, closely adjacent said beam path to provide large mutual inductive coupling between the electromagnetic Wave and the electron beam, means coupled to said transmission line towards the end adjacent said gun for directly applying the electromagnetic wave to said line and means coupled to said line at the other end for removing the electromagnetic wave, said transmission line including means for causing the wave to propagate more slowly than electrons in said beam.
  • a travelling wave amplifier tube comprising an electron gun and a collector electrode defining a beam path therebetween, a transmission line including two coaxial conductors arranged parallel to the beam path for propagating an electromagnetic wave along said beam path in the direction from said gun to said collector electrode, the space between said conductors being separated from said beam path by one of said conductors the one of said coaxial conductor adjacent said beam path being subdivided to provide mutual inductive coupling between the Wave and the beam, means coupled to said line towards the end adjacent said gun for directly applying the electromagnetic wave to said line, and means coupled to said line towards the other end for abstracting energy from said electromagnetic wave said transmission line being adapted to propagate the wave more slowly than electrons in said beam.
  • a travelling wave amplifier tube comprising an electron gun and a collector electrode defining a beam path therebetween, a transmission line including two coaxial conductors arranged coaxially about the beam path for propagating an electromagnetic wave along said beam path in the direction from said gun to said collector electrode, the inner of said coaxial conductors being arranged about said beam path and being adapted to provide mutual inductive coupling between the wave and the beam, means coupled to said line towards the end adjacent said gun for directly applying the electromagnetic wave to said line and means coupled to said line at the other end for removing the electromagnetic wave from said line said transmission line including means for causing the wave to propagate more slowly than electrons in said beam.
  • a travelling wave amplifier tube in which the inner conductor comprises a plurality of parallel wires arranged coaxially about the beam path.
  • a travelling wave amplifier tube according to claim 3 in which the last-mentioned means comprises a material of high dielectric constant placed between the inner and the outer conductors.
  • a travelling wave amplifier tube comprising an electron gun and a collector electrode defining an electron beam path, therebetween, an envelope arranged about said gun and said collector electrode and said beani path, a transmission line including two coaxial conductors arranged coaxially about the beam path for propagating an electromagnetic wave along said beam path in the direction from said gun to said collector electrode, the inner of said coaxial conductors including a. plurality of parallel wires arranged coaxially about said beam path, means coupled to said transmission line at the end adjacent said gun for directly applying the electromagnetic wave to said transmission line, means coupled to said transmission line at the end adjacent said collector electrode for removing the electromagnetic wave from said transmission line, and a material 8. of high dielectric constant placed between said inner and outer conductors for causing thewave to propagate along said transmission line more slowly than electrons in said beam.
  • a travelling wave amplifier tube according to claim 6 in which said material of high dielec trio constant is formed integrally with said envelope.
  • An electron discharge device in which the ratio of the radius of the outer coaxial conductor to that of the inner is approximately 3.5;
  • a travelling wave amplifier tube comprising an electron gun and a collector electrode defining :a beam path therebetween, and a transmission line including two coaxial conductors arranged coaxially about the'beam path for propagating an electromagnetic Wave along said beam path in the direction from said gun to said collector electrode, the inner of said coaxial conductors being arranged about said beam path and being adapted to provide mutual inductive coupling between the wave and the beam, means coupled to said transmission line at the end adjacent said gun for directly applying the electromagnetic wave to said transmission line, means coupled to said transmission line at the end adjacent said collector electrode for removing the electromagnetic wave from said transmission line, said transmission line being adapted to propagate the wave more slowly than electrons in said beam.
  • a travelling wave amplifier tube in which the outer conductor of said transmission line comprises a helix of wire whereby the wave transmitted along said transmission line is propagated more slowly than electrons in said beam.
  • a travelling wave amplifier tube comprising an electron gun and a collector electrode defining a beam path therebetween, an envelope enclosing said gun and collector electrode and arranged coaxially about said beam path, a transmission line including two coaxial conductors arranged coaxially about the beam path for propagating an electromagnetic wave along said beam path in the direction from said gun to said collector electrode, the inner of said coaxial conductors including a plurality of parallel conductor wires arranged coaxially about said beam path inside said envelope for providing mutual inductive coupling between the wave and the beam, the outer of said coaxial conductors comp-rising a helix of wire arranged about said envelope, means coupled to said transmission line at the end adjacent said gun for directly applying the electromagnetic wave to said transmission line, and means coupled to said transmission line at the end adjacent said collector electrode for removing the electromagnetic wave from said transmission lines 12.
  • a travelling wave amplifier tube comprising a cylindrical electron gun and a collector electrode defining a cylindrical electron beam path therebetween, a transmission line including two coaxial conductors arranged coaxially inside said beam path for propagating. an electromagnetic wave along said beam path in the direction from said gun to said collector electrode, the outer of said coaxial conductors being subdivided and disposed closely adjacent said beam path to provide mutual inductive coupling between the wave and the beam, means coupled to said transmission line at the end adjacent said gun for directly applying the electromagnetic wave to said transmission line, and means coupled to said transmission line at the end adjacent said collector electrode for removing the electromagnetic wave from said transmission line, said transmission line including means for causing the wave to propagate more slowly than electrons in said beam.
  • a travelling wave amplifier tube in which said outer conductor comprises a plurality of parallel wires arranged coaxially inside said beam path.
  • a travelling wave amplifier tube in which said means for causing the wave to propagate slowly comprises a material of high dielectric constant arranged between the coaxial conductors.
  • a travelling wave amplifier tube in which the ratio of the radius of the outer coaxial conductor to that of the inner coaxial conductor is approximately 3.5.
  • a travelling wave amplifier tube comprising a cylindrical electron gun and a collector electrode defining an electron beam path therebetween, an envelope enclosing said electron gun and collector electrode and beam path, a transmission line including two coaxial conductors arranged coaxially inside said beam path for propagating an electromagnetic wave along said beam path in the direction from said gun to said collector electrode, the outer of said coaxial conductors including a plurality of parallel wires arranged coaxially inside said beam path for providing mutual inductive coupling between the Wave and the beam, means associated with said transmission line at the end adjacent said gun for ing the electromagnetic wave each comprises an extension of said transmission line through said envelope one at the end adjacent said electron gun and the other at the end adjacent said collector electrode.

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  • Microwave Amplifiers (AREA)
US3325A 1948-01-20 1948-01-20 Beam traveling wave amplifier tube Expired - Lifetime US2654047A (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
BE486897D BE486897A (no) 1948-01-20
US3325A US2654047A (en) 1948-01-20 1948-01-20 Beam traveling wave amplifier tube
GB26285/48A GB675187A (en) 1948-01-20 1948-10-08 Beam travelling wave amplifier tube
FR979203D FR979203A (fr) 1948-01-20 1949-01-15 Amplificateurs à ondes progressives

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US3325A US2654047A (en) 1948-01-20 1948-01-20 Beam traveling wave amplifier tube

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US2654047A true US2654047A (en) 1953-09-29

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BE (1) BE486897A (no)
FR (1) FR979203A (no)
GB (1) GB675187A (no)

Cited By (25)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2740917A (en) * 1952-04-12 1956-04-03 Hughes Aircraft Co Electron stream amplifier tube
US2748268A (en) * 1955-06-15 1956-05-29 Hughes Aircraft Co Backward-wave oscillator mixer
US2749472A (en) * 1952-01-02 1956-06-05 Univ Leland Stanford Junior Travelling wave tubes
US2750529A (en) * 1952-03-12 1956-06-12 Bell Telephone Labor Inc Electron discharge device
US2800602A (en) * 1951-06-05 1957-07-23 Univ Leland Stanford Junior Low noise electron discharge tubes
US2802141A (en) * 1949-03-16 1957-08-06 Raytheon Mfg Co Electron discharge devices
US2809321A (en) * 1953-12-30 1957-10-08 Hughes Aircraft Co Traveling-wave tube
US2813221A (en) * 1950-10-02 1957-11-12 Rca Corp Electron beam traveling-wave tube
US2833955A (en) * 1954-02-04 1958-05-06 Itt Traveling wave electron discharge devices
US2840752A (en) * 1954-12-30 1958-06-24 Bell Telephone Labor Inc Backward wave tube
US2844753A (en) * 1953-04-03 1958-07-22 Bell Telephone Labor Inc Traveling wave tube
US2845571A (en) * 1953-04-17 1958-07-29 Kazan Benjamin Electrostatically focused traveling wave tube
US2850671A (en) * 1952-01-24 1958-09-02 Raytheon Mfg Co Magnetron amplifiers
US2851631A (en) * 1955-03-07 1958-09-09 Hughes Aircraft Co Traveling wave tube of high forward wave impedance
US2871451A (en) * 1953-12-21 1959-01-27 Bell Telephone Labor Inc Modulated backward wave oscillator
US2878412A (en) * 1953-09-04 1959-03-17 Sperry Rand Corp Travelling wave oscillator
US2888597A (en) * 1952-12-13 1959-05-26 Csf Travelling wave oscillator tubes
US2891191A (en) * 1953-11-18 1959-06-16 Bell Telephone Labor Inc Backward wave tube
US2899596A (en) * 1959-08-11 Wide band mixing system
US2916657A (en) * 1952-05-17 1959-12-08 Bell Telephone Labor Inc Backward wave amplifier
US2921224A (en) * 1954-12-06 1960-01-12 Bell Telephone Labor Inc Traveling wave tube amplifier
US2939998A (en) * 1957-08-16 1960-06-07 Zenith Radio Corp Direct radiation vacuum tube
US2959706A (en) * 1958-06-23 1960-11-08 Bell Telephone Labor Inc Electron discharge device
US3382399A (en) * 1965-05-06 1968-05-07 Army Usa Modified traveling wave tube
US4362968A (en) * 1980-06-24 1982-12-07 The United States Of America As Represented By The Secretary Of The Navy Slow-wave wideband cyclotron amplifier

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1063720B (de) * 1954-05-22 1959-08-20 Telefunken Gmbh Elektrische Entladungsroehre nach dem Lauffeldprinzip

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2122538A (en) * 1935-01-22 1938-07-05 American Telephone & Telegraph Wave amplifier
US2233126A (en) * 1933-10-23 1941-02-25 Rca Corp Device for and method of controlling high frequency currents
US2300052A (en) * 1940-05-04 1942-10-27 Rca Corp Electron discharge device system
US2367295A (en) * 1940-05-17 1945-01-16 Bell Telephone Labor Inc Electron discharge device
US2511407A (en) * 1947-01-09 1950-06-13 Csf Amplifying valve of the progressive wave type
US2541843A (en) * 1947-07-18 1951-02-13 Philco Corp Electronic tube of the traveling wave type
US2578434A (en) * 1947-06-25 1951-12-11 Rca Corp High-frequency electron discharge device of the traveling wave type

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2233126A (en) * 1933-10-23 1941-02-25 Rca Corp Device for and method of controlling high frequency currents
US2122538A (en) * 1935-01-22 1938-07-05 American Telephone & Telegraph Wave amplifier
US2300052A (en) * 1940-05-04 1942-10-27 Rca Corp Electron discharge device system
US2367295A (en) * 1940-05-17 1945-01-16 Bell Telephone Labor Inc Electron discharge device
US2511407A (en) * 1947-01-09 1950-06-13 Csf Amplifying valve of the progressive wave type
US2578434A (en) * 1947-06-25 1951-12-11 Rca Corp High-frequency electron discharge device of the traveling wave type
US2541843A (en) * 1947-07-18 1951-02-13 Philco Corp Electronic tube of the traveling wave type

Cited By (25)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2899596A (en) * 1959-08-11 Wide band mixing system
US2802141A (en) * 1949-03-16 1957-08-06 Raytheon Mfg Co Electron discharge devices
US2813221A (en) * 1950-10-02 1957-11-12 Rca Corp Electron beam traveling-wave tube
US2800602A (en) * 1951-06-05 1957-07-23 Univ Leland Stanford Junior Low noise electron discharge tubes
US2749472A (en) * 1952-01-02 1956-06-05 Univ Leland Stanford Junior Travelling wave tubes
US2850671A (en) * 1952-01-24 1958-09-02 Raytheon Mfg Co Magnetron amplifiers
US2750529A (en) * 1952-03-12 1956-06-12 Bell Telephone Labor Inc Electron discharge device
US2740917A (en) * 1952-04-12 1956-04-03 Hughes Aircraft Co Electron stream amplifier tube
US2916657A (en) * 1952-05-17 1959-12-08 Bell Telephone Labor Inc Backward wave amplifier
US2888597A (en) * 1952-12-13 1959-05-26 Csf Travelling wave oscillator tubes
US2844753A (en) * 1953-04-03 1958-07-22 Bell Telephone Labor Inc Traveling wave tube
US2845571A (en) * 1953-04-17 1958-07-29 Kazan Benjamin Electrostatically focused traveling wave tube
US2878412A (en) * 1953-09-04 1959-03-17 Sperry Rand Corp Travelling wave oscillator
US2891191A (en) * 1953-11-18 1959-06-16 Bell Telephone Labor Inc Backward wave tube
US2871451A (en) * 1953-12-21 1959-01-27 Bell Telephone Labor Inc Modulated backward wave oscillator
US2809321A (en) * 1953-12-30 1957-10-08 Hughes Aircraft Co Traveling-wave tube
US2833955A (en) * 1954-02-04 1958-05-06 Itt Traveling wave electron discharge devices
US2921224A (en) * 1954-12-06 1960-01-12 Bell Telephone Labor Inc Traveling wave tube amplifier
US2840752A (en) * 1954-12-30 1958-06-24 Bell Telephone Labor Inc Backward wave tube
US2851631A (en) * 1955-03-07 1958-09-09 Hughes Aircraft Co Traveling wave tube of high forward wave impedance
US2748268A (en) * 1955-06-15 1956-05-29 Hughes Aircraft Co Backward-wave oscillator mixer
US2939998A (en) * 1957-08-16 1960-06-07 Zenith Radio Corp Direct radiation vacuum tube
US2959706A (en) * 1958-06-23 1960-11-08 Bell Telephone Labor Inc Electron discharge device
US3382399A (en) * 1965-05-06 1968-05-07 Army Usa Modified traveling wave tube
US4362968A (en) * 1980-06-24 1982-12-07 The United States Of America As Represented By The Secretary Of The Navy Slow-wave wideband cyclotron amplifier

Also Published As

Publication number Publication date
BE486897A (no)
FR979203A (fr) 1951-04-24
GB675187A (en) 1952-07-09

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