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Publication numberUS3760305 A
Publication typeGrant
Publication dateSep 18, 1973
Filing dateOct 30, 1972
Priority dateOct 30, 1972
Publication numberUS 3760305 A, US 3760305A, US-A-3760305, US3760305 A, US3760305A
InventorsLandry N, Mason R
Original AssigneeRca Corp
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Dielectrically loaded waveguide assembly
US 3760305 A
A body of gyromagnetic material closely fitted within a flexible waveguide is supported by means of an external clamp and a pair of dielectric guides.
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Claims  available in
Description  (OCR text may contain errors)

iliiiie ason et al.

iaies [191 [451 Sept. 18,1973


Norman Richard Landry, Willingboro, both of NJ.

Assignee: RCA Corporation, New York, N.Y.

Filed: Oct. 30, 1972 Appl. No.: 302,183

US. Cl. 333/95 R, 333/24.l, 333/98 R Int. Cl. H015) 3/12, HOlp 1/00 Field of Search 333/24.l, 24.2, 95 R,

333/95 A, 98 R, 81 B; 138/108; 174/12 References Cited UNITED STATES PATENTS 5/1958 Weisbaum 333/24.2

3,316,507 4/1967 Heitcr 333/24.2 X 3,408,597 10/1968 3,617,960 11/1971 Lavedan, .lr. 333/24.1

I Primary Examiner-Rud0lph V. Rolinec Assistant Examiner-Wm. H. Punter Attorney-Edward .1. Norton et al.

[57] ABSTRACT A body of gyromagnetic material closely fitted within a flexible waveguide is supported by means of an external clamp and a pair of dielectric guides.

8 Claims, 4 Drawing Figures DIELECTRICALLY LOADED WAVEGUIDE ASSEMBLY This invention relates to a waveguide assembly and more particularly to waveguide structures which inpresence of a D.C. magnetic field and an RF. magnetic field is similar to that in a mechanical gyroscope. When the dielectric body is ferrite or garnet material and is properly biased such such as by a D.C. magnetic field, the waveguide assembly may provide the functions of phase shifting, isolating and limiting of radio frequency signal waves applied to the waveguide section.

The waveguides are conventionally made by extruding, machining, or casting tubes to a required cross sectional dimension. This dimension is dependent on the frequency and the modes of the propagating wave. A dielectric body of ferrite or garnet material is dimensioned so as to properly fit within the waveguide. The ferrite or garnet materials are generally fragile and have a different thermal expansion coefficient from that of thewaveguides. This can cause fracture of these materials if they are simply bonded to the waveguide. In addition, the garnet materials are magnetostrictive. The stresses on the garnet material caused by differences in thermal expansion or contractionbetween the garnet and the waveguide as when these materials and the waveguide are bonded or are otherwise fixed to each other along their length can drastically effect the magnetic field within the garnet. Consequently, changes in the D.C. bias cause unpredictable changes in the amount of phase shift, for example, efiected by the waveguide section. Although ferrite material has no appreciable magnetostrictive effect, at certain frequencies such as at S-band, the remanent level changes rather drastically with substantial change in temperature rendering this ferrite material impractical for many applications at S-band. It is therefore desirable that a means be provided by which ferrite and garnet material particularly may be attached to and supported in a waveguide section such that the forces of magnetostriction and thermal expansion are minimized to prevent fracture of the material or large changes in the magnetic field.

Briefly, the present invention provides a waveguid assembly, for example, a rectangular tube of flexible conductive material. A body of dielectric material having at least a portion of gyromagnetic material is spaced FIG. 2 is a perspective drawing of an assembled microwave phase shifter with a portion of the waveguide removed for illustration.

FIG. 3 is an end view of the waveguide assembly of FIG. 2.

FIg. 4 is a cross section of the waveguide assembly of FIG. 2 taken in the 4-4 plane.

Referring to FIG. 1, there is illustrated a dielectric body 10. At the center portion of the body 10 is a member 12 of gyromagnetic material. The term gyromagnetic material refers to those materials, both garnets and ferrites, which exhibit a gyromagnetic effect when a D.C. and an RF. magnetic field are applied thereacross. At either end of the member 12 of gyromagnetic material are bonded high dielectric non-magnetic transformer members 11 and 13 to form the total dielectric body 10. These dielectric transformer bodies 11 and 13 act, when the body 10 is placed within a rectangular waveguide, as matching elements for the input and output ends of the waveguide assembly.

Referring to FIGS. 2, 3 and 4, the body 10 is placed within a hollow rectangular waveguide 16 such that the body 10 including the dielectric transformer members 11 and 13 and the center member 12 is centered between the narrow walls 21 and 23 of the waveguide 16 and extends between the broad walls 17 and 19 of the waveguide 16.. The pair of dielectric transformer bodies 11 and 13 are at the opposite ends of the rectangular waveguide 16. The hollow rectangular waveguide 16 is made up of electrically conductive material. The pair of opposing broad walls 17 and 19 of the waveguide 16 are separated by a distance which is normally slightly less than the heighth dimension of the dielectric body 10 which is gripped between the opposing broad walls 17 and 19 of the waveguide 16. The waveguide walls are made of a material of such thickness and elastic properties to allow the body to be placed within the waveguide with the walls imposing a force on the body 10 which neither exceeds an acceptable value not is less than sufficient to provide a close fit of the gyrobetween the opposed broad walls of the rectangular following drawings wherein:

FIG. 1 is a perspective view of a dielectric body ineluding a gyromagnetic material member and dielectric matching members.

magnetic body 10 between the waveguide walls 17 and 19. The waveguide walls 17, 19, 21 and 23 are thin enoughto follow the contour of the body 10 but yet be fairly rugged. For example, this waveguide 16 can be formed by drawing a tube through a die to a thickness of 0.014 inch. The particular material used, for example, may be 606,1 T3 aluminum as sold by Aluminum Co. of America.

A pair of L-shaped members 27 and 29 with interlocking portions 27a, 27b, 29a and 29b are fitted to the outside of walls 17, 19, 21 and 23 of the waveguide 16 near the dielectric end 13. See detail in FIG. 3. The members 27 and 29 are attached to each other by means of a pair of screws'31 and 33 extending through members 27 and 29 respectively and being tightened against threads 29c and 27c. located in members 29 and 27 respectively. As the L-shaped members 27 and 29 are fitted closer by tightening the screws 31 and 33, the broad walls 17 and 19 of the tube are brought in closer contact with dielectric member 13 of body 10 so as to clamp the dielectric member 13 between the broad walls 17 and 19 at one end of the waveguide 16. Since the member 12 of gyromagnetic material is bonded to the dielectric body 13 and dielectric member 11 is bonded to member 12 the whole body 10 is fixed at one end to waveguide 16.

Remote from the clamping end of the body 10 at the dielectric member 13 is located a pair of dielectric spacers 35 and 37. See FIGS. 2 and 4. These spacers 35 and 37 fit on either side of the gyromagnetic member 12 and inside the waveguide 16 in such a way to prevent lateral displacement (toward or away from narrow walls 21 and 23) of the gyromagnetic member 12 and body 10 within the waveguide 16. Referring to FIG. 4, the spacers 35 and 37 are configured with small protrusions 35a and 370 which may fit to small holes 41 and 43 in the side walls 23 and 21 respectively of the waveguide 16 to thus lock these spacers into position. By making these spacers 35 and 37 U-shaped with the free end against the body and the middle portion against the narrow waveguide wall, air can flow through the waveguide 16 to permit cooling.

In the operation of the device as a phase shifter, for example, changes in the amount of phase shift for waves propagating along the waveguide assembly can be provided by changing the amount of DC magnetic field bias applied in the direction of arrow 14 in Flg. 2. This D.C. magnetic field bias is applied perpendicular to broad wall 17. The DC. magnetic field bias can be achieved by a magnet located above the wall 17 or below wall 19 or can be achieved by making the member 12 a toroid. When the member 12 of body 10 is a toroid, a biasing wire, not shown, extends along the length of the member 12 within the center of the member 12 and a DC. current pulse is coupled to the wire.

What is claimed is:

l. A waveguide assembly comprising:

a waveguide of flexible conductive material and having a pair of opposite walls,

a body of dielectric material spaced between the opposed walls of the waveguide,

an external clamp coupled to the outside of the waveguide near one end of the body and the waveguide so as to force the opposed walls of the waveguide against a portion of the body and hold the body, and

dielectric means coupled between the waveguide walls and a point along said body remote from the clamping portion for preventing transverse movement of said body within said waveguide but permitting longitudinal movement of said body.

2. The combination claimed in claim 1 wherein said dielectric means includes a pair of dielectric spacers wherein one of said spacers is located in the region between a third wall of said waveguide and said body and the second spacer is located in the region between a fourth wall of said waveguide and said body.

3. The combination claimed in claim 2 wherein said spacer is U-shaped with the free ends against the body and the middle portion against the waveguide wall.

4. The combination claimed in claim 3 wherein said spacers include means for locking said spacers within said waveguide.

5. The combination claimed in claim 1 wherein said dielectric body includes a portion of gyromagnetic material and a portion of non-magnetic dielectric material.

6. The combination claimed in claim 5 wherein said gyromagnetic material is garnet.

7. The combination claimed in claim 6 wherein only said non-magnetic dielectric material portion of said body is clamped between said waveguide walls.

8. The combination claimed in claim 1 wherein said waveguide is rectangular and is made of thin walled aluminum tubing, said third and fourth walls being the opposite narrow walls of said waveguide, said clamp arranged to force the opposite broad walls of said waveguide against said body to hold said body.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US2834947 *Apr 25, 1955May 13, 1958Bell Telephone Labor IncField displacement isolator
US3316507 *Sep 10, 1965Apr 25, 1967Bell Telephone Labor IncMagnetostrictive tuning of the magnetic parameters of gyromagnetic materials used in wave transmission devices
US3408597 *May 11, 1966Oct 29, 1968Bell Telephone Labor IncNonreciprocal gyromagnetic waveguide device with heat transfer means forming a unitary structure
US3421116 *Dec 13, 1966Jan 7, 1969Us NavyUtilizing a resilient waveguide wall
US3617960 *Aug 25, 1969Nov 2, 1971Sperry Rand CorpWaveguide partially formed of a flexible member for obtaining uniform minimal pressure contact with a load therein
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3849746 *Oct 18, 1973Nov 19, 1974Us NavyMounting assembly for ferrimagnetic core in waveguide phase shifter
US3952267 *Jan 3, 1975Apr 20, 1976The United States Of America As Represented By The Secretary Of The NavyMetal spray forming of waveguide for phase shifter case
US4001733 *Aug 18, 1975Jan 4, 1977Raytheon CompanyFerrite phase shifter having conductive material plated around ferrite assembly
US4338609 *Dec 15, 1980Jul 6, 1982Rca CorporationShort horn radiator assembly
US4349790 *Apr 17, 1981Sep 14, 1982Rca CorporationCoax to rectangular waveguide coupler
US8855451Jul 20, 2012Oct 7, 2014Duke UniversityOptical isolator
US9170440Mar 14, 2014Oct 27, 2015Duke UniversityPolymer optical isolator
US20110311181 *Dec 22, 2011Duke UniversityOptical Isolator
U.S. Classification333/239, 333/248, 333/24.1
International ClassificationH01P1/19, H01P1/18
Cooperative ClassificationH01P1/19
European ClassificationH01P1/19