US3771076A - Combined electromagnetic waveguide and mode filter - Google Patents
Combined electromagnetic waveguide and mode filter Download PDFInfo
- Publication number
- US3771076A US3771076A US00222477A US3771076DA US3771076A US 3771076 A US3771076 A US 3771076A US 00222477 A US00222477 A US 00222477A US 3771076D A US3771076D A US 3771076DA US 3771076 A US3771076 A US 3771076A
- Authority
- US
- United States
- Prior art keywords
- component
- waveguide
- mode filter
- electrically conductive
- composite
- 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
Links
- 239000002131 composite material Substances 0.000 claims abstract description 31
- 230000003014 reinforcing effect Effects 0.000 claims abstract description 22
- 239000011810 insulating material Substances 0.000 claims abstract description 13
- 230000005540 biological transmission Effects 0.000 claims description 22
- 239000003365 glass fiber Substances 0.000 claims description 10
- 239000012777 electrically insulating material Substances 0.000 claims description 8
- 239000012799 electrically-conductive coating Substances 0.000 claims description 8
- 239000011347 resin Substances 0.000 claims description 8
- 229920005989 resin Polymers 0.000 claims description 8
- 239000000463 material Substances 0.000 claims description 6
- 229910000831 Steel Inorganic materials 0.000 claims description 3
- 239000010959 steel Substances 0.000 claims description 3
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 10
- 239000002184 metal Substances 0.000 description 7
- 229910052751 metal Inorganic materials 0.000 description 7
- 229910052802 copper Inorganic materials 0.000 description 5
- 239000010949 copper Substances 0.000 description 5
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 4
- 238000000034 method Methods 0.000 description 4
- 239000011248 coating agent Substances 0.000 description 3
- 238000000576 coating method Methods 0.000 description 3
- 238000010276 construction Methods 0.000 description 3
- 229910002804 graphite Inorganic materials 0.000 description 3
- 239000010439 graphite Substances 0.000 description 3
- 230000001629 suppression Effects 0.000 description 2
- 241000272194 Ciconiiformes Species 0.000 description 1
- 239000009970 Helixor Substances 0.000 description 1
- 239000004698 Polyethylene Substances 0.000 description 1
- 230000004323 axial length Effects 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 239000004020 conductor Substances 0.000 description 1
- 238000007787 electrohydrodynamic spraying Methods 0.000 description 1
- 238000009713 electroplating Methods 0.000 description 1
- 238000005530 etching Methods 0.000 description 1
- 238000010348 incorporation Methods 0.000 description 1
- 238000003754 machining Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- -1 polyethylene Polymers 0.000 description 1
- 229920000573 polyethylene Polymers 0.000 description 1
- 239000012779 reinforcing material Substances 0.000 description 1
- 238000009877 rendering Methods 0.000 description 1
- 238000001771 vacuum deposition Methods 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01P—WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
- H01P1/00—Auxiliary devices
- H01P1/16—Auxiliary devices for mode selection, e.g. mode suppression or mode promotion; for mode conversion
- H01P1/163—Auxiliary devices for mode selection, e.g. mode suppression or mode promotion; for mode conversion specifically adapted for selection or promotion of the TE01 circular-electric mode
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01P—WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
- H01P3/00—Waveguides; Transmission lines of the waveguide type
- H01P3/12—Hollow waveguides
- H01P3/13—Hollow waveguides specially adapted for transmission of the TE01 circular-electric mode
Definitions
- a substantially rigid, composite electromagnetic waveguide component comprises at least one waveguide of circular cross-section comprising a continuous, circumferential electrically cohductive layer extending over a part of the length of the component and a mode filter extending over the remaining part of the component.
- the mode filter is constituted by a plurality of mutually spaced, circumferentially continuous, electrically conductive rings or at least one electrically conductive helix with closely spaced turns, the mode filter and waveguide overlying an inner tubular layer of insulating material.
- a reinforcing insulating body preferably surrounds the component and renders it substantially rigid.
- a mode filter is positioned at one end of the component and the other end is shaped to form a socket.
- waveguides of circular cross-section for use in effecting communication over a long distance by conveying microwave signals along the waveguides arranged continuously along an appropriate transmission path.
- a substantially rigid, composite electromagnetic waveguide component comprising at least one waveguide of circular cross-section comprising a continuous, circumferential electrically conductive layer extending over a part, preferably a major part, of the length of the component and a mode filter extending over the remaining part of the component.
- the component includes, at one or each of its ends, means for connecting the composite waveguide component to one end of a composite waveguide component of similar form or to one end of a substantially rigid electromagnetic waveguide of circular cross-section having a continuous circumferential electrically conductive layer extending throughout its length.
- the composite electromagnetic waveguide component of the present invention has the important advantages that it combines in a single component the electrical performance of a waveguide of circular crosssection having a continuous, circumferential electrically conductive layer and the suppression effect of a mode filter and that a plurality of such waveguide components can be used in a simple manner to build upa transmission path which has mode filters distributed at frequent intervals along its length and which, by virtue of the substantial rigid construction of the waveguide component, has greater dimensional accuracy than transmission paths having separately formed mode filters incorporated at intervals.
- the mode filter is preferably surrounded by a layer or layers of lossy material, for instance glass fibre tape containing graphite or other electrically conductive material, and to provide the component with the required rigidity the waveguide or waveguides and mode filter are preferably surrounded by a plurality of layers of resin bonded glass fibre or of other suitable reinforcing material.
- the component may have an outer conductive screen, for instance a thin steel jacket or a braided wire sleeve.
- the means by which adjacent waveguide components are connected preferably takes the form of a spigot and socket connection.
- a spigot and socket connection between adjacent components may be effected by a separate unit making a spigot and socket connection with each component but preferably at one end of each component, the component is shaped to form a socket in which the opposite end of another waveguide component will fit.
- the component has a single mode filter located at or near one end the socket is preferably formed at theother end of the. component.
- the waveguide component of the present invention may itself constitute a separate connector unit for making a spigot and socket connection between adjacent waveguide components, or between adjacent substantially rigid electromagnetic waveguides of circular cross-section each having a continuous circumferential electrically conductive layer extending throughout its length, and for this purpose the component preferably has a single mode filter located between its ends which are shaped to form sockets into which the ends of adjacent waveguides will fit.
- the invention also includes transmission path built up of a plurality of waveguide components in accordance with the invention connected end to end.
- the invention further includes transmission path built up of a plurality of substantially rigid electromagnetic waveguides of circular cross-section each having a a continuous circumferential electrically conductive layer extending throughout its length, at least one pair of adjacent waveguides being connected end to end by a waveguide component in accordance with the invention.
- composite electromagnetic waveguide component inaccordance with the invention which includes the steps of applying a continuous circumferential layer of electrically conducting metal to a mandrel of circular crosssection and, before or after removing the mandrel from the electrically conductive layer so formed, forming over a portion of the length of the component a mode filter by removing a part of the layer over said portion to leave a plurality of mutually spaced, circumferentially continuous rings or at least one helix with closely spaced turns of electrically conducting metal.
- the dimensions of the continuous rings or of the helixor helices so formed will be such that the mode filter of the component will suppress to at least a substantial extent the propagation of unwanted modes in a transmission path of which the component forms a part.
- the inner tubular layer of insulating material on which the continuous electrically conductive layer and the mode filter are supported may be preformed or may be applied as a coating to the internal surface of the component and in both cases preferably it is inserted into or applied to the component after the mandrel is removed but it may be initially applied over the mandrel and may itself constitute the outer part of the mandrel on which the electrically conductive layer or layers and mode filter are formed.
- a thin layer of material that will facilitate easy removal of the mandrel, for instance a coating of graphite, is preferably applied to the mandrel before forming the continuous layer or layers and mode filter.
- the or each continuous circumferential electrically conductive layer may be formed by electro plating, spraying or vacuum deposition of a metal, e.g. copper, or by any other suitable method.
- the mode filter may be formed by initially applying to the mandrel a plurality of mutually spaced, circumferentially continuous rings or at least one helix with closely spaced turns of a resist from which the electrically conductive metal can be easily removed, e.g.
- the continuous electrically conductive layer may be formed over the whole length of the component and, after the mandrel has been removed but before the insulating tubular layer is inserted, appropriate parts of the conductive layer removed by machining or by other means to form the mode filter.
- a layer of electrically insulating material for example resin bonded glass fibre, will normally be applied over the mode filter in accordance with normal practice and a layer or layers of lossy material, for instance carbon impregnated resin bonded glass fibre, applied over the insulating layer.
- the radial thickness of the lossy material will be such that in conjunction with the continuous rings or helix or helices the required impedance for the suppression of unwanted modes of propagation is provided.
- Layers of electrically insulating material, for instance resin bonded glass fibre, to provide the required rigidity will normally be applied throughout the length of the component, such layers being applied, andwhere necessary cured, before the mandrel is removed.
- An outer screen is preferably applied overall.
- the mandrel which is preferably of metal, may be of cylindrical cross-section throughout its length but, where one end of the component to be formed is to constitute a socket, the mandrel may be of appropriate increased cross-section at one end.
- a substantially rigid mode filter of circular crosssection including a plurality of mutually spaced, circumferentially continuous rings of an electrically conductive coating, or at least one helix with closely spaced turns of an electrically conductive coating, overlying an inner tubular layer of insulating material and a method of forming said mode filter is the subject of our co-pending Patent Application No. 222,478 filed on the same day as the present application.
- FIG. 1 is a sectional side view of one form of waveguide component with the inner tubular insulating layer omitted;
- FIG. 2 is a fragmental diagrammatic sectional side view of a wall of the waveguide component shown in FIG. 1, drawn on an enlarged scale;
- FIG. 3 is a sectional side view of a second form of waveguide component with the inner tubular insulating layer omitted;
- FIG. 4 is a fragmental diagrammatic representation of one form of transmission path built up of waveguide components as shown in FIG. 3;
- FIG. 5 is a fragmental diagrammatic representation of a second form of transmission path builtup of a third form of waveguide component in accordance with the invention.
- FIG. 6 is a similar view of a third form of transmission path built up of a fourth form of waveguide component in accordance with the invention.
- the waveguide component shown in FIGS. 1 and 2 is of circular cross-section and has an overall length of 3 metres (9.85 ft), an internal diameter of 5 cms (1.97 in) and an overall wall thickness of 5.2 mm (0.20 in). It comprises a waveguide comprising a continuous circumferential copper layer 4 having a thickness of Sum (0.0002 in) and a length of 2. metres ft) and a mode filter extending over the remaining part of the component and comprising 2400 copper rings 3 each having a thickness of 5 m (0.0002 in) and an axial length of 0.1 mm (0.004 in), the spacing between adjacent rings being 0.02 mm (0.00079 in).
- the copper layer 4 and copper rings 3 overlie an inner tubular layer 2 of polyethylene having a radial thickness of 0.2 mm (0.0079 in).
- a body 7 built up of layers of resin bonded, glass fibre is applied to the component throughout its length to the overall wall thickness of 5 mm (0.197 in), the body rendering the component substantially rigid.
- the waveguide component 11 shown in FIG. 3 includes 2400 copper rings 13 constituting a mode filter and a copper layer 14 constituting a waveguide and is of similar construction to the waveguide component shown in FIG. 1 except that, at the end of the component remote from the mode filter, the bore of the component is enlarged to form a socket 18.
- the socket 18 has an internal diameter such that an end of a waveguide component of similar form, or an end of a substantially rigid waveguide of circular cross-section having an overall diameter equal to that of the component, will make a tight spigot and socket joint in the socket.
- adjacent waveguide components are connected end to end with the end at which the mode filter 13 is formed making a spigot and socket joint in the socket 18 of the adjacent component.
- the transmission path so formed is substantially rigid throughout its length.
- the transmission path shown in FIG. 5 is built up of waveguide components 21 of a third form in which a copper helix with closely spaced turns constituting the mode filter 23 is positioned between copper layers constituting waveguides 24 and each end of the component is enlarged to form sockets 28 and of waveguide components 31 of a fourth form which is similar to that of the components 21 but which is not enlarged at its ends.
- Components 21 and 31 are arranged alternately along the length of the transmission path with each end of a component 31 making a spigot and socket joint with socket 28 of a component 21.
- the transmission path shown in FIG. 6 is built up of waveguide components 31 each having its mode filter 33 positioned between waveguides 34 and neighbouring ends of the components fit into and make spigot and socket joints with opposite ends of a tubular connector unit 30 of insulating material.
- the transmission paths shown in FIGS. 5 and 6 are both substantially rigid throughout their lengths.
- Electromagnetic waveguide components in accordance with the invention have the important advantage of high dimensional accuracy because the dimensions of the bore of the component are determined by the dimensions of the mandrel which can be accurately ground to the required size.
- a further advantage arises from the fact that the outer screen, when present, can be substantially thinner than the-conventional metal sheath or jacket hitherto employed in substantially rigid waveguides and consequently the component is therefore light in weight and easy to install.
- transmission path of any desired length can be formed with mode filters provided at frequent intervals by interconnecting by simple spigot and socket joints a plurality of similar composite waveguide components.
- a substantially rigid, composite electro-magnetic waveguide component of circular cross-section comprising an inner tubular layer of insulating material; at least one waveguide comprising a continuous circumferential electrically conductive coating extending over a part of the length of the outer surface of the tubular layer; a mode filter constituted by a plurality of mutually spaced, circumferentially continuous, electrically conductive rings or at least one electrically conductive helix with closely spaced turns, extending over the remaining part'of the outer surface of the tubular layer;
- a reinforcing body of electrically insulating material which surrounds, and extends beyond at least one end of, the component formed by the waveguide or waveguides and mode filter and renders the component substantially rigid, the or each projecting end of the reinforcing body being shaped to form a socket with a substantially smooth internal surface in which an end of a waveguide or of another waveguide component can make a spigot and socket joint.
Landscapes
- Control Of Motors That Do Not Use Commutators (AREA)
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB381171 | 1971-02-03 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US3771076A true US3771076A (en) | 1973-11-06 |
Family
ID=9765347
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US00222477A Expired - Lifetime US3771076A (en) | 1971-02-03 | 1972-02-01 | Combined electromagnetic waveguide and mode filter |
Country Status (3)
| Country | Link |
|---|---|
| US (1) | US3771076A (Direct) |
| FR (1) | FR2124408A1 (Direct) |
| GB (1) | GB1351872A (Direct) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4145673A (en) * | 1977-07-19 | 1979-03-20 | Societe Anonyme Dite Compagnie Industrielle Des Telecommunications Cit-Alcatel | Multiplexer for millimetric waves |
| US4231042A (en) * | 1979-08-22 | 1980-10-28 | Bell Telephone Laboratories, Incorporated | Hybrid mode waveguide and feedhorn antennas |
| US4246584A (en) * | 1979-08-22 | 1981-01-20 | Bell Telephone Laboratories, Incorporated | Hybrid mode waveguide or feedhorn antenna |
| US9531048B2 (en) | 2013-03-13 | 2016-12-27 | Space Systems/Loral, Llc | Mode filter |
Citations (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2544842A (en) * | 1943-06-23 | 1951-03-13 | James L Lawson | Overload protection of highfrequency receivers |
| US2564007A (en) * | 1947-11-14 | 1951-08-14 | Bell Telephone Labor Inc | Coupling for wave guides |
| DE820455C (de) * | 1949-11-01 | 1951-11-12 | Siemens & Halske A G | Verbindungsstelle fuer Hohlrohrkabel |
| DE866960C (de) * | 1944-03-12 | 1953-02-12 | Siemens Ag | Hohlkabel fuer ortsveraenderliche Kurzwellen-Sende- und Empfangsanlagen zur UEbertragung von Frequenzen zwischen 1 und 10 Gigahertz |
| US2644028A (en) * | 1942-05-04 | 1953-06-30 | Edwin J Bernet | Expansion joint for coaxial lines |
| US2695255A (en) * | 1950-10-25 | 1954-11-23 | Douglas W Avery | Method of expanding an elastic liner against the inner surface of a pipe |
| US2848695A (en) * | 1954-03-15 | 1958-08-19 | Bell Telephone Labor Inc | Electromagnetic wave transmission |
| US2966643A (en) * | 1957-08-23 | 1960-12-27 | Bell Telephone Labor Inc | Electromagnetic wave guide structure |
| US3003020A (en) * | 1958-12-19 | 1961-10-03 | Bell Telephone Labor Inc | Joining assembly for wave guide sections or the like |
| US3066268A (en) * | 1955-08-05 | 1962-11-27 | Int Standard Electric Corp | Electric waveguide construction |
| US3110001A (en) * | 1957-08-23 | 1963-11-05 | Bell Telephone Labor Inc | Unwanted mode absorbing circular wave guide having circumferential gaps coupled, by intermediate dielectric, to external dissipative sheath |
| US3149295A (en) * | 1962-05-28 | 1964-09-15 | Dow Chemical Co | Waveguide joining by criss-cross welding of extended flanges |
| US3176249A (en) * | 1959-11-30 | 1965-03-30 | Marconi Co Ltd | Waveguide impedance matching transitions while maintaining effective cross-section unchanged |
| US3492607A (en) * | 1965-12-08 | 1970-01-27 | Nat Res Dev | Electromagnetic waveguides |
| US3573681A (en) * | 1969-03-12 | 1971-04-06 | Bell Telephone Labor Inc | Helical waveguide formed from dielectric ribbon having symmetrically disposed conductive strips on opposite sides |
-
1971
- 1971-02-03 GB GB381171*[A patent/GB1351872A/en not_active Expired
-
1972
- 1972-02-01 US US00222477A patent/US3771076A/en not_active Expired - Lifetime
- 1972-02-02 FR FR7203515A patent/FR2124408A1/fr not_active Withdrawn
Patent Citations (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2644028A (en) * | 1942-05-04 | 1953-06-30 | Edwin J Bernet | Expansion joint for coaxial lines |
| US2544842A (en) * | 1943-06-23 | 1951-03-13 | James L Lawson | Overload protection of highfrequency receivers |
| DE866960C (de) * | 1944-03-12 | 1953-02-12 | Siemens Ag | Hohlkabel fuer ortsveraenderliche Kurzwellen-Sende- und Empfangsanlagen zur UEbertragung von Frequenzen zwischen 1 und 10 Gigahertz |
| US2564007A (en) * | 1947-11-14 | 1951-08-14 | Bell Telephone Labor Inc | Coupling for wave guides |
| DE820455C (de) * | 1949-11-01 | 1951-11-12 | Siemens & Halske A G | Verbindungsstelle fuer Hohlrohrkabel |
| US2695255A (en) * | 1950-10-25 | 1954-11-23 | Douglas W Avery | Method of expanding an elastic liner against the inner surface of a pipe |
| US2848695A (en) * | 1954-03-15 | 1958-08-19 | Bell Telephone Labor Inc | Electromagnetic wave transmission |
| US3066268A (en) * | 1955-08-05 | 1962-11-27 | Int Standard Electric Corp | Electric waveguide construction |
| US2966643A (en) * | 1957-08-23 | 1960-12-27 | Bell Telephone Labor Inc | Electromagnetic wave guide structure |
| US3110001A (en) * | 1957-08-23 | 1963-11-05 | Bell Telephone Labor Inc | Unwanted mode absorbing circular wave guide having circumferential gaps coupled, by intermediate dielectric, to external dissipative sheath |
| US3003020A (en) * | 1958-12-19 | 1961-10-03 | Bell Telephone Labor Inc | Joining assembly for wave guide sections or the like |
| US3176249A (en) * | 1959-11-30 | 1965-03-30 | Marconi Co Ltd | Waveguide impedance matching transitions while maintaining effective cross-section unchanged |
| US3149295A (en) * | 1962-05-28 | 1964-09-15 | Dow Chemical Co | Waveguide joining by criss-cross welding of extended flanges |
| US3492607A (en) * | 1965-12-08 | 1970-01-27 | Nat Res Dev | Electromagnetic waveguides |
| US3573681A (en) * | 1969-03-12 | 1971-04-06 | Bell Telephone Labor Inc | Helical waveguide formed from dielectric ribbon having symmetrically disposed conductive strips on opposite sides |
Non-Patent Citations (2)
| Title |
|---|
| Barlow, H. E. M. A Method of Changing the Dominant Mode in a Hollow Metal Waveguide & its Application to Bends, IEE, Vol. 106B, Supp. 13, 1959, pp. 100 105. * |
| Rose, C. F. P., Research Models of Helix Waveguides, Bell System Tech. Jr., 5 1958, pp. 679 687. * |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4145673A (en) * | 1977-07-19 | 1979-03-20 | Societe Anonyme Dite Compagnie Industrielle Des Telecommunications Cit-Alcatel | Multiplexer for millimetric waves |
| US4231042A (en) * | 1979-08-22 | 1980-10-28 | Bell Telephone Laboratories, Incorporated | Hybrid mode waveguide and feedhorn antennas |
| US4246584A (en) * | 1979-08-22 | 1981-01-20 | Bell Telephone Laboratories, Incorporated | Hybrid mode waveguide or feedhorn antenna |
| US9531048B2 (en) | 2013-03-13 | 2016-12-27 | Space Systems/Loral, Llc | Mode filter |
Also Published As
| Publication number | Publication date |
|---|---|
| GB1351872A (en) | 1974-05-01 |
| FR2124408A1 (Direct) | 1972-09-22 |
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