US3361926A - Interdigital stripline teeth forming shunt capacitive elements and an array of inductive stubs connected to adjacent teeth - Google Patents

Interdigital stripline teeth forming shunt capacitive elements and an array of inductive stubs connected to adjacent teeth Download PDF

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US3361926A
US3361926A US350516A US35051664A US3361926A US 3361926 A US3361926 A US 3361926A US 350516 A US350516 A US 350516A US 35051664 A US35051664 A US 35051664A US 3361926 A US3361926 A US 3361926A
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Prior art keywords
circuit
interdigital
teeth
line
wave
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US350516A
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George K Farney
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SFD LAB Inc
S-F-D LABORATORIES Inc
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SFD LAB Inc
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Priority to US350516A priority Critical patent/US3361926A/en
Priority to DE1791268A priority patent/DE1791268C2/de
Priority to DE1965S0095670 priority patent/DE1491448B2/de
Priority to JP1310465A priority patent/JPS5340868B1/ja
Priority to GB10009/65A priority patent/GB1068646A/en
Priority to FR8523A priority patent/FR1438337A/fr
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J29/00—Details of cathode-ray tubes or of electron-beam tubes of the types covered by group H01J31/00
    • H01J29/02—Electrodes; Screens; Mounting, supporting, spacing or insulating thereof
    • H01J29/10—Screens on or from which an image or pattern is formed, picked up, converted or stored
    • H01J29/18—Luminescent screens
    • H01J29/28—Luminescent screens with protective, conductive or reflective layers
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J23/00—Details of transit-time tubes of the types covered by group H01J25/00
    • H01J23/16—Circuit elements, having distributed capacitance and inductance, structurally associated with the tube and interacting with the discharge
    • H01J23/24—Slow-wave structures, e.g. delay systems
    • H01J23/28—Interdigital slow-wave structures; Adjustment therefor
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J23/00—Details of transit-time tubes of the types covered by group H01J25/00
    • H01J23/36—Coupling devices having distributed capacitance and inductance, structurally associated with the tube, for introducing or removing wave energy
    • 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
    • H01J25/42—Tubes in which an electron stream interacts with a wave travelling along a delay line or equivalent sequence of impedance elements, and with a magnet system producing an H-field crossing the E-field
    • 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
    • H01J25/42—Tubes in which an electron stream interacts with a wave travelling along a delay line or equivalent sequence of impedance elements, and with a magnet system producing an H-field crossing the E-field
    • H01J25/44—Tubes in which an electron stream interacts with a wave travelling along a delay line or equivalent sequence of impedance elements, and with a magnet system producing an H-field crossing the E-field the forward travelling wave being utilised

Definitions

  • FIG. l3 INTERDIGITAL STRIPLINE TEETH FORMING SHUNT CAPACITIVE ELEMENTS AND AN ARRAY OF INDUCTIVE STUBS CONNECTED TO ADJACENT TEETH Filed March 9, 1964 3 Sheets-Sheet 3 FIG. l3
  • the stripline slow wave circuit is formed by a pair of comb-like structures having their teeth interdigitated.
  • the interdigitated teeth form iterative shunt capacitive elements in the stripline.
  • An array of inductive stubs connect adjacent teeth to a conductive support wall.
  • the adjacent stubs which are interconnected at the support wall, form iterative inductive elements connected in shunt with the stripline for resonating the capacitive elements at a frequency determinative of the low frequency cut-off of the passband of the slow wave circuit.
  • An elec tron stream is electronically interacted with the electric fields of the resonated shunt capacitive element to produce a microwave output signal.
  • a transmission line is connected to the slow wave circuit via a mitered tooth thereof for obtaining a broadband match to the slow wave circuit.
  • the interdigital stripline is recessed from the electron stream at the wave turn-around portions of the meandering wave path, formed by the circuit, to reduce electronic interaction in the turn-around field regions of the circuit for increased efficiency.
  • the present invention relates in general to slow wave circuits and more particularly to an improved interdigital slow wave circuit and impedance matching circuit for same.
  • Such tubes are used as transmitting tubes in radar, communication links, radio astronomy, etc.
  • interdigital slow Wave circuits see US. 2,816,248 issued Dec. 10, 1957.
  • an interdigital line is used for backward wave tubes such as backward wave amplifiers or oscillators.
  • backward wave tubes such as backward wave amplifiers or oscillators.
  • Recently it has been proposed to reactively load the conductors in series therewith and to interact the beam alternately with both the series and shunt voltages of the interdigital line see US. patent application No. 350,504 filed Mar. 9, 1964 and assigned to the same assignee as the present invention.
  • This latter type of circuit yields a fundamental forward wave space harmonic with improved electronic bandwidth.
  • the interdigital slow wave circuit can now be used tin both forward and backward wave tubes operating in the fundamental space harmonic mode.
  • interdigital line circuits One of the problems associated with interdigital line circuits is their relatively low interaction impedance of 20-30 ohms which leads to rather low electronic efficiencies for crossed field tubes of this type of 20-30%.
  • Another problem common to amplifiers using interdigital lines is to find matching structures that will permit coupling wave energy onto and from the slow wave circuit without introducing unwanted reflections of wave energy which often lead to unwanted oscillation of the tube thereby restricting the useful bandwidth of the amplifier to some value substantially below the electronic bandwidth of the circuit obtainable in the presence of an improved match.
  • the meandering circuit formed by the interdigital line contains portions where the electric field vector of the wave energy on the circuit is parallel to the static magnetic field lines. For such a case, the electrons of the stream which see this electric field are driven axially out of the interaction region and are lost from the stream thereby reducing electronic efficiency of the tube.
  • an iterative inductive reactive loading is added to the interdigital line in shunt with the iterative shunt capacity elements of the line to increase the electronic interaction impedance thereof.
  • the reactive loading takes the form of stub supports for the line which stubs also serve to cool the circuit by conduction of heat from the circuit to a heat sink.
  • the present invention provides an improved matching structure which permits impedance matching to and from the interdigital line over a broad band of frequencies as of :25% of the center band frequency of the tube over which power output varies by only 3 db.
  • the present invention provides centrally located tabs on the interaction side of the interdigital line in crossed field tubes such that those side portions of the meandering line where the electric field vector is parallel to the magnetic field are removed from the stream of charged particles whereby stream particles are not lost from the stream due to electric fields in the turn around portions of the interdigital line.
  • the inductive shunt loading is continuously distributed over the interdigital line and does not constitute an iterative inductive shunt loading as provided by the inductive stubs herein proposed.
  • the iterative inductive stubs connected in shunt with the iterative capacitive shunting elements of the interdigital line permits the tube designer to trade bandwidth for impedance to any desired extent between the limits of that of a non-shunt inductively loaded interdigital line and that of the split folded waveguide.
  • the tube designer need merely alter the relative dimensions of the stub supports and thereby alter the amount of inductance connected in shunt with the shunting capacity elements and correspondingly shift the low frequency cut off of the slow wave circuit to any extent desired.
  • interdigital line means that the two-wire line is of the strip line type wherein the conductors forming the meandering transmission line have a width taken in a direction normal to the .dominant mode electric field vector which is more than half the characteristic distance between the conductors taken along the direction of the electric field vector.
  • Such strapped magnetrons are narrow band devices because the two wire'transmission line formed by such narrow straps sets up strong standing wave patterns because of the iterative large jumps in characteristic impedance of the two-wire line formed by such narrow straps and wide vanes.
  • the principal object of the present invention is to provide improved interdigital slow wave circuits and im-' pedance matches for same whereby tubes with enhanced performance are obtained.
  • One feature of the present invention is the provision of an interdigital line circuit with iterative inductive reactive loading connected in shunt with the iterative capacity portions of the circuit whereby the electronic interaction impedance of the circuit is increased leading to increased efficiency and gain.
  • Another feature of the present invention is the same as the preceding feature wherein the iterative reactive loading comprises inductive thermally conductive stub members interconnecting the circuit to a heat sink whereby cooling of the circuit is enhanced.
  • Another feature of the present invention is a novel strip line impedance matching structure for matching into and/or out of an interdigital line, the novel strip line being characterized by one of the conductors having a mitered corner at the point of connection to the interdigital line whereby a substantially refiectionless broad band connection to the circuit is obtained.
  • Another feature of the present invention is the provision of centrally disposed tabs on the interaction side of the interdigital line such tabs extending from the line toward the cathode electrode whereby the Wave turn around portions of the interdigital line, containing electric field lines parallel to the static magnetic field of crossed field tubes, are removed from the beam field interaction region to enhance electronic efficiency.
  • FIG. 1 is a perspective view of a prior art interdigital slow wave circuit
  • FIG. 2 is an equivalent circuit for the prior art interdigital circuit of FIG. 1;
  • FIG. 4 is a transverse sectional view of two alternative embodiments of the interdigital slow wave circuit of the present invention, both embodiments having the same transverse section;
  • FIG. 5 is a longitudinal sectional view of the structure of FIG. 4 taken along lines 55 in the direction of the arrows showing one embodiment of the present invention
  • FIG. 7 is an equivalent circuit for the structure of FIGS. 46;
  • FIG. 9 is a longitudinal view, partly broken away, of the structure of FIG. 4 taken along lines 99, showing the second alternative embodiment
  • FIG. 10 is an equivalent circuit for the structure of FIGS. 4, 8 and 9;
  • FIG. 11 is an enlarged perspective view, partly in phantom, showing the matching structure of the present invention.
  • FIG. 12(a1) is a transverse view of the structure of FIG. 11 taken along lines 12--12;
  • FIG. 12(b) is a reduced flattened out plan view of the meander strip line of FIG. 12(a);
  • FIG. 13 is a longitudinal sectional view of a tube using the slow wave circuit of the present invention.
  • FIG. 15 is a transverse sectional view of the structure of FIG. 14 taken along lines 15-15.
  • the circuit consists of a pair of interdigitated conductive combs A and B, each having a backbone with depending tooth portion.
  • One comb A forms one conductor of a strip transmission line.
  • the other comb B forms the other conductor of the strip transmission line.
  • Wave energy propagating on the circuit meanders back and forth across a stream of charged particles, typically electrons, indicated at line 1, which is projected adjacent the structure or through aligned openings in the structure, not shown.
  • FIG. 2 An equivalent circuit forv the interdigital line of FIG. 1 is shown at FIG. 2.'The dotted line represents the path of charged particles and they alternately interact with the capacitive shunt voltages of the circuit developed between the relatively large mutually opposed areas of adjacent teeth of the interdigitated conductive combs A and B and forming the iterative capacity shunting elements of the circuit.
  • the dispersion characteristic for the circuit of FIG. 1 is shown by dotted line 2 in the 40-13 diagram of FIG. 3.
  • Curve 2 shows the circuit to have a fundamental backward wave space harmonic mode of operation and, of course, it is accompanied by other higher order space harmonics. It is well known, for example that forward wave interaction can be obtained with the first forward space harmonic, at reduced voltage and interaction impedance from that of the fundamental backward wave. From the dispersion characteristic it can be seen that the circuit is extremely broad band extending from DC. or near DC. to an upper cut-off frequency 01 The upper cutoff frequency m corresponds to resonance of the series inductive elements L with the shunting capacity elements C in the equivalent circuit and corresponds to 11' phase shift along path I, see FIG. 1.
  • the useable part of the dispersion curve is defined by that portion of line 2 between points X and Y. This portion of the curve corresponds to practical beam voltages and has a rather high group velocity, i.e., proportional to the slope of curve 2.
  • the electronic interaction impedance of the circuit is inversely proportional to the group velocity and, therefore, the interdigital line of FIG. 1 has a typical interaction impedance of 20-3O ohms which leads to relatively low efficiencies of 20 to 30%.
  • an inductive reactive load L is connected across the shunting capacitance C of the transmission line.
  • the inductance L of the shunting element is proportioned to resonate with the shunting capacitance C of the line at a frequency, m which determines the low frequency cutoff for the transmission line.
  • a transmission line cannot propagate unless the series reactance, such as produced by L is of opposite sign to the reactance of the shunting elements, L and C.
  • the inductive element L is preferably provided by shorted sections of two-wire line formed by generally parallel conductive stubs 3, as of copper, projecting away from the circuit. Stubs 3 interconnect the conductive teeth 4 near the central region thereof, with a conductive wall member 5 as of copper. The wall 5 shorts the strip transmission line formed by adjacent parallel stubs 3.
  • the stubs 3 are proportioned in length d, and width, w, such that the total electrical length, A from the tip of the vane like teeth 4 to the wall 5, is less than A /4 at the low frequency cut-off of the passband of the interdigital circuit.
  • This dimension, a is characteristically equal to x /4 for the split folded waveguide.
  • Wall preferably forms the vacuum envelope of the tube thereby also serving as a heat sink for cooling of the conductive teeth 4.
  • the stubs 3 also give greater mechanical rigidity to the interdigital line.
  • the dispersion curve for the stub supported interdigital line of FIGS. 4-7 is shown by curve 6 of FIG. 3. It will be seen that the useable portion of this curve between points x'-y' has a slope which is substantially less than the slope of the non-inductively shunted transmission line dispersion curve 2. Therefore, the group velocity of the stub supported strip line has been reduced and the electronic interaction impedance substantially increased. In a typical example the stubs 3 increased the interaction impedance from 20-30 ohms to 60-80 ohms and produced a commensurate increase in electronic efliciency from 20-30% to 45-50%.
  • the slow wave circuit includes an interdigital meander line having a structure quite similar to that of FIGS. 4, 5 and 6 except that the teeth 4 of the interdigitated combs A and B are bifurcated at 7.
  • the bifurcation of the teeth 4 introduces an additional inductive reactive loading in series with the two conductors A and B of the strip line.
  • This reactive loading at 7 puts the stream of charged particles into electromagnetic interaction with the voltages developed across the series inductance L' as indicated in FIG. 10 Where the dotted line indicates the beam path.
  • the type of electronic interaction obtained in this type of circuit will be called alternating series and shunt interaction because the beam particles alternately interact with the series and shunt voltages developed in the circuit by elements U and L -C, respectively.
  • the stub supports 3 add an inductive element L in shunt with the shunting capacitive element C to resonate the shunting capacity at a frequency w' which is determinative of the low frequency cut off of the circuit.
  • the stub supports 3 also introduce an additional inductance in series with conductors A and B. This additional inductance gets added in the equivalent circuit to L and the inductance of reactive element 7 to produce L' L is substantially greater than L such that the high frequency cut off m is substantially reduced to w' and the new dispersion curve is as shown in solid line at 9.
  • the electrical result of the stub support 3 is to raise the low frequency cut off w' and lower the high frequency cut off thereby substantially decreasing the slope of the dispersion curve and raising the interaction impedance with attendant increase in efficiency and gain.
  • the stubs 3 also have the effect of placing the entire dispersion curve 9 within the range of practical beam voltages between V and V such that substantially the entire bandwidth of the circuit may be used for electronic interaction.
  • the stubs 3 serve to cool the circuit by conduction to the wall 5.
  • the amount of inductance added by the stubs 3 is regulated by judicious choice of dimensions a, d, and w, as before described.
  • adjacent stub members 3 which are in shunt with the line form a strip line feed.
  • the vane or tooth 4 connected to one of the stubs is mitered in height h to form a mitered corner at 11 such that it has substantially reduced height at the edge remote from the support wall 5 as compared to its height at the edge adjacent the wall 5.
  • the stub 3 is also mitered in width w as produced by a straight line continuation of the mitered corner 11 of the tooth 4.
  • the stub 3 at its connection to the tooth 4 is mitered at an angle of 45 to the axis of the longitudinal axis or centerline of the stub 3, as more clearly shown in FIG. 12, with the mitered edge 11 passing through the centerline Q of the stub at the point of its connection 12 to the tooth 4.
  • the mitered corner matching structure has initially been described in FIG. 11 with regard to an unsevered interdigital line.
  • the interdigital line will be severed and the matching structure will be disposed adjacent the sever 31 (see FIG. 14) either at the input and/or output terminal of the slow wave circuit.
  • the sever 31 is typically a solid conductive block with transverse section the same as that of the circuit. Therefore, in practice the sever 31 serves as the last tooth 4" of the slow wave circuit, such sever tooth 4" being preferably much thicker than the adjacent circuit teeth 4.
  • mitered tooth will be deemed to include such a mitered portion of the circuit sever.
  • This sever structure 31 is shown by phantom lines in FIG.
  • the sever block 31 is mitered at 11 only for that portion immediately adjacent the slow wave circuit.
  • the depth of the mitered corner 11 in a typical embodiment is only twice the tooth thickness of the other teeth of the slow wave circuit.
  • a capacitive matching ramp 15 is centrally disposed of the waveguide 13 for matching the impedance of the guide 13 to the impedance of the iris 14.
  • Wave energy is coupled from the waveguide 13 via iris 14 into the strip line between stubs 3.
  • the mitered corner 11 of stub 3 and tooth 4 causes the wave energy to make a right angle turn as indicated by the arrow of FIG. 11 and thence it continues around the interdigital line in the conventional manner.
  • the mitered corner 11 provides a near reflectionless match, i.e. less than 1% reflected energy corresponding to a VSWR less than 1.2 over a 25-50% bandwidth.
  • a similar matching structure without the mitered corner 11 has a VSWR of 2:1 corresponding to 10% reflected energy which would be considered generally unsatisfactory for broadband, high gain tube operation.
  • FIG. 12 there is shown another embodiment of the present invention. More particularly there is shown the provision of tab portions 4 of the teeth 4 which extend out from the teeth 4 a distance, g, toward the cathode structure and thereby define the interaction side edge portion of the interdigital strip line.
  • the tabs 4' extend over the central portion of the interdigital line and terminate in axial extent at or near the end of the overlapping portion of the teeth 4.
  • the spacing, k, between the axial end of the tabs 4' and the backbone portion of the interdigital line is the same as the spacing, 0, between the free end portions of the conductive teeth 4 and the other conductor of the meandering strip line, see FIGS. 5 and 8.
  • g is approximately equal to O
  • k is approximately equal to O
  • p the width of the strip meander line, is at least three times greater than g.
  • the characteristic impedance Z of the strip line of FIGS. 12(b) and (c) is given by the following expression where O is the spacing between conductors of the strip line and b is the transverse extent of the conductors. In one portion of the strip line of FIG. 12(0) b is equal to p, for another portion b is equal to p+g.
  • the characteristic impedance of the meandering strip line of FIG. 12(1)) will vary from In a typical example Z varies from 709 to 909 yielding a VSWR of 1.28 which corresponds to approximately 1% reflected power at the discontinuities in Z This amount of reflected power is acceptable. However, of reflected power corresponding to a 100% jump in Z would not be considered acceptable for broad band operation.
  • FIGS. 13 and 14 there is shown a tube structure employing the features of the present invention. More specifically a typical X-band crossed field amplifier tube structure is shown.
  • the tube includes a hollow cylindrical vacuum envelope Wall member 5 as of copper.
  • An array of stub 3 supported vane or teeth 4 project radially inwardly from the inner side of the wall 5 to form with annular conductors A and B an interdigital line of the type shown and previously described with respect to FIGS. 4-7.
  • Conductors A and B, as of copper, extend over to and are conductively joined, as by brazing, to the wall '5.
  • a hollow cylindrical cold cathode emitter 17 is coaxially disposed centrally of the interdigital circuit.
  • the cathode is made of a material having a high secondary electron emission ratio such as berryllium copper.
  • a pair of annular end hats 18 are disposed at the axial ends of the emitter 17. Conventional high voltage feed through insulator assemblies, not shown, bring the cathode stem 24 through the vacuum envelope to the emitter.
  • a pair of hollow cylindrical magnetic pole pieces 25 as of soft iron are axially spaced apart on opposite sides of the emitter 17 and interdigital lines A and B to provide an axial magnetic field as of 5000 gauss throughout the electrons interaction gap 26 between emitter 17 and the interdigital line.
  • Permanent C-shaped magnets join to the pole pieces 25 externally of the tubes vacuum envelope to provide the magnetomotive force for the axial magnetic field.
  • a pair of waveguides 13 project radially away from the main body wall member 5.
  • Suitable gas-tight wave permeable window members seal off the outer extremities of the waveguides 13 and include flange assemblies to permit the tube to be connected to waveguides for applying to and or extracting wave energy from the tube.
  • Dumbbell irises 14 extend substantially entirely across the waveguide 13 and communicate with stubs 3 through wall 5.
  • Irises 14 are matched to the waveguide 13 via capacitive matching ramps 15 which have a slope, S, of approximately
  • the irises 14 are relatively thick, i.e., they have a length, 1, which is more than a small fraction of their minimum transverse dimensions, c, in order to provide broadband low Q coupling since the Q of the iris 14 is inversely proportional to its thickness to transverse ratio, t/c.
  • the circuit is severed at 31 by a metallic sector subtending approximately 54 of arc to provide a drift space 32 such that the .re-entrant beam can debunch before reentering into interaction with the circuit.
  • the tube had an operating range of 8.5 to 9.6 gc. as a backward Wave amplifier, an average power output of 1 kw., cathode to anode voltage of 28 to 35 kv., a synchronous voltage of 35 kv., and a gain of 20 db.
  • the circuit teeth 4 had a height, h, of 0.280", a total length, a, including stu-b of 0.285, a stub length, d, of 0.125", a stub width, w, of 0.125", and a tooth thickness of 0.030", and 0.030" spacing between teeth, a tab length, g, of 0.040, and a total of 34 teeth in the circuit.
  • a high frequency tube apparatus including, an interdigital stripline slow Wave circuit having an operating passband, said slow wave circuit including a pair of interdigitated conductive comb structures having interdigitated tooth portions and a pair of spaced backbone portions, said interdigitated tooth portions of said circuit forming iterative capacitive means for developing a series of capacitive shunt voltages in said circuit, inductive stub means forming iterative inductive reactive sections of transmission line interconnecting teeth of one comb to the adjacent teeth of the other comb for developing inductive reactive loading connected in shunt with said stripline for resonating said capacitative means with said inductive stub means at a frequency determinative of the low frequency cut-off of said passband, means for projecting a stream of charged particles adjacent said slow wave circuit for cumulative electronic interaction with successive voltages developed by said iterative resonated shunting means, whereby the electronic interaction impedance of said slow Wave circuit is increased, means forming a conductive Wall extending adjacent to and along said interdigitated slow wave circuit, said
  • interconnecting sections of transmission line include conductive stub members connected to said teeth in a plane generally midway between the backbones of said combs and extending away from said teeth in said plane to form generally T shaped composite tooth and stub members, and conductive means interconnecting adjacent ones of said stub members toform the shunting inductive reactance in parallel with the capacitance between adjacent teeth.
  • said teeth are plate-like members, with their broad faces disposed in mutually opposed relation, and including a plurality of conductive stub members connected to the side edge portions of said plate-like teeth along one side thereof and extending away from said teeth in the same plane thereof, and wherein at least one conductor of said second transmission line is defined by one of said stub members.
  • the apparatus according to claim 8 including, a conductive Wall directed along said slow wave circuit,
  • the apparatus according to claim 12 including an iris communicating through said wall in registry with the space between said two conductors of said strip line for Wave energy coupling thereto.
  • the apparatus according to claim 13 including a hollow rectangular waveguide disposed in registry with said coupling iris for wave energy communication therewith, and means disposed in said waveguide for matching the impedance of said waveguide to the impedance of said lI'lS.
  • turn around fringing field removing means comprises means for causing edge portions of said interdigital slow wave circuit, which are removed from said turn around portions of said wave path, to project inwardly toward said stream more than circuit edge portions at the turn around portions of the wave path.
  • said inwardly projecting edge portions are tabs which inwardly project from said strip line to an extent which is less than 50% of the width of the strip line at said turn around portions, whereby wave reflections along said meandered strip line are reduced.

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US350516A 1964-03-09 1964-03-09 Interdigital stripline teeth forming shunt capacitive elements and an array of inductive stubs connected to adjacent teeth Expired - Lifetime US3361926A (en)

Priority Applications (6)

Application Number Priority Date Filing Date Title
US350516A US3361926A (en) 1964-03-09 1964-03-09 Interdigital stripline teeth forming shunt capacitive elements and an array of inductive stubs connected to adjacent teeth
DE1791268A DE1791268C2 (de) 1964-03-09 1965-02-25 Verzögerungsleitung für eine Lauffeldröhre mit Anschluß einer zweiten Übertragungsleitung. Ausscheidung aus: 1491448
DE1965S0095670 DE1491448B2 (de) 1964-03-09 1965-02-25 Verzoegerungsleitung fuer eine lauffeldroehre
JP1310465A JPS5340868B1 (de) 1964-03-09 1965-03-08
GB10009/65A GB1068646A (en) 1964-03-09 1965-03-09 Slow wave circuits and discharge devices employing same
FR8523A FR1438337A (fr) 1964-03-09 1965-03-09 Structure à retard interdigitale avec dispositif d'adaptation d'impédance

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US350516A US3361926A (en) 1964-03-09 1964-03-09 Interdigital stripline teeth forming shunt capacitive elements and an array of inductive stubs connected to adjacent teeth

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US3361926A true US3361926A (en) 1968-01-02

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US (1) US3361926A (de)
JP (1) JPS5340868B1 (de)
DE (2) DE1491448B2 (de)
FR (1) FR1438337A (de)
GB (1) GB1068646A (de)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3436594A (en) * 1965-12-15 1969-04-01 Sfd Lab Inc Slow wave circuit having an array of half wave resonators coupled via an array of quarter wave resonators
US3653744A (en) * 1970-05-22 1972-04-04 Lockheed Aircraft Corp Optical modulator utilizing a slow wave circuit
US3953759A (en) * 1975-03-20 1976-04-27 Varian Associates Interdigital slow wave circuit for electron tubes
DE19525199A1 (de) * 1995-07-11 1997-01-16 Licentia Gmbh Verzögerungsleitung für eine Wanderfeldröhre und Verfahren zu deren Herstellung
US20110052208A1 (en) * 2009-08-31 2011-03-03 Kabushiki Kaisha Toshiba Optoelectronic wiring film and optoelectronic wiring module
CN105869971A (zh) * 2016-05-23 2016-08-17 电子科技大学 一种平顶型正弦波导慢波结构

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US2679615A (en) * 1946-12-31 1954-05-25 Sylvania Electric Prod Electron discharge device
US2881348A (en) * 1952-12-19 1959-04-07 Csf Delay line for traveling wave tubes
US2920227A (en) * 1952-06-28 1960-01-05 Csf Ladder type delay line

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2679615A (en) * 1946-12-31 1954-05-25 Sylvania Electric Prod Electron discharge device
US2920227A (en) * 1952-06-28 1960-01-05 Csf Ladder type delay line
US2881348A (en) * 1952-12-19 1959-04-07 Csf Delay line for traveling wave tubes

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3436594A (en) * 1965-12-15 1969-04-01 Sfd Lab Inc Slow wave circuit having an array of half wave resonators coupled via an array of quarter wave resonators
US3653744A (en) * 1970-05-22 1972-04-04 Lockheed Aircraft Corp Optical modulator utilizing a slow wave circuit
US3953759A (en) * 1975-03-20 1976-04-27 Varian Associates Interdigital slow wave circuit for electron tubes
DE2611498A1 (de) * 1975-03-20 1976-10-07 Varian Associates Elektronenroehre mit interdigitalleitung
DE19525199A1 (de) * 1995-07-11 1997-01-16 Licentia Gmbh Verzögerungsleitung für eine Wanderfeldröhre und Verfahren zu deren Herstellung
US20110052208A1 (en) * 2009-08-31 2011-03-03 Kabushiki Kaisha Toshiba Optoelectronic wiring film and optoelectronic wiring module
CN105869971A (zh) * 2016-05-23 2016-08-17 电子科技大学 一种平顶型正弦波导慢波结构

Also Published As

Publication number Publication date
DE1491448B2 (de) 1972-07-13
FR1438337A (fr) 1966-05-13
DE1491448A1 (de) 1969-06-12
JPS5340868B1 (de) 1978-10-30
DE1791268C2 (de) 1974-04-11
GB1068646A (en) 1967-05-10
DE1791268B1 (de) 1973-09-20

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