# US 2014/0197908 A1 · Polarization coupler > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0197908 A1 - Document ID: US20140197908A1 - Status: Published application - Kind: A1 - Application number: 14/238,658 - Filed: 2012-11-16 - Published: 2014-07-17 - Earliest claimed: 2011-11-17 - Assignees: Mitsubishi Electric Corporation - Inventors: Hiroto Ado; Shuji Nuimura; Tomohiro Mizuno; Hidenori Yukawa; Tetsu Owada; Takaaki Kimata - Web page: https://patentgrep.com/patent/US20140197908A1 ## CPC - H01P 3/127: with a circular, elliptic, or parabolic cross-section - H01P 1/161: sustaining two independent orthogonal modes, e.g. orthomode transducer {(combining or separating polarisations and frequencies H01P1/2131)} - H01P 1/2131: {with combining or separating polarisations} - H01P 5/082: {Transitions between hollow waveguides of different shape, e.g. between a rectangular and a circular waveguide} - H01P: WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE (operating at optical frequencies G02B) ## Abstract A polarization coupler includes: connector waveguide that connects circular waveguide with quadrangular waveguide arranged in an axial direction of circular waveguide and having short side shorter than an inner diameter of circular waveguide; flat conductor wall formed over connector and circular waveguides, and dividing the inside of connector and circular waveguides arranged parallel to an extending direction of long side of quadrangular waveguide; first inclined surface formed on inner wall of connector waveguide at a position facing one surface of conductor wall, and inclined toward conductor wall as coming closer to quadrangular waveguide; second inclined surface formed on the inner wall of connector waveguide at a position facing the other surface of conductor wall, and inclined toward conductor wall as coming closer to quadrangular waveguide; and coupling hole, formed in circular waveguide, for extracting one polarization-divided by conductor wall out of electromagnetic waves propagated through circular waveguide. ## Claims ### Claim 1 A polarization coupler comprising: a circular waveguide; a quadrangular waveguide that is arranged in an axial direction of the circular waveguide, and has a short side shorter than an inner diameter of the circular waveguide; a connector waveguide that connects the quadrangular waveguide with the circular waveguide; a flat conductor wall that is formed over the connector waveguide and the circular waveguide, and divides the inside of the connector waveguide and the circular waveguide arranged parallel to a direction where a long side of the quadrangular waveguide extends; a first inclined surface that is formed on an inner wall of the connector waveguide at a position facing one surface of the conductor wall, and inclined toward the conductor wall as coming closer to the quadrangular waveguide; a second inclined surface that is formed on the inner wall of the connector waveguide at a position facing the other surface of the conductor wall, and inclined toward the conductor wall as coming closer to the quadrangular waveguide; and a coupling hole that is formed in the circular waveguide, and extracts one that is polarization-divided by the conductor wall out of electromagnetic waves propagated through the circular waveguide, wherein the connector waveguide is configured by: an arc-shaped first wall surface; an arc-shaped second wall surface that faces the first wall surface; the first inclined surface; and the second inclined surface. ### Claim 2 (depends on 1) The polarization coupler according to claim 1, wherein the first inclined surface and the second inclined surface each have a stepwise shape. ### Claim at position 3 3-5. (canceled) ### Claim 6 (depends on 1) The polarization coupler according to claim 1, wherein the connector waveguide is configured by: an arc-shaped first wall surface that has the same diameter as the inner diameter of the circular waveguide; an arc-shaped second wall surface that faces the first wall surface and has the same diameter as the inner diameter of the circular waveguide; the first inclined surface; and the second inclined surface. ### Claim 7 (depends on 1) The polarization coupler according to claim 1, wherein the connector waveguide is configured at a part connected to the circular waveguide by: an arc-shaped first wall surface that has the same diameter as the inner diameter of the circular waveguide; an arc-shaped second wall surface that faces the first wall surface and has the same diameter as the inner diameter of the circular waveguide; the first inclined surface; and the second inclined surface, wherein the first wall surface and the second wall surface each have a diameter that increases from the circular waveguide side toward the quadrangular waveguide side. ### Claim 8 (depends on 1) The polarization coupler according to claim 1, wherein the long side of the quadrangular waveguide is shorter than the inner diameter of the circular waveguide. ### Claim 9 (depends on 1) The polarization coupler according to claim 1, wherein the one surface and the other surface of the conductor wall in the connector waveguide each are formed in a trapezoid shape. ### Claim 10 (depends on 8) The polarization coupler according to claim 8, wherein the connector waveguide is configured at a part connected to the circular waveguide by: an arc-shaped first wall surface; an arc-shaped second wall surface that faces the first wall surface; the first inclined surface; and the second inclined surface, wherein a distance between the first wall surface and the second wall surface decreases from the circular waveguide side toward the quadrangular waveguide side. ### Claim 11 (depends on 9) The polarization coupler according to claim 9, wherein the connector waveguide is configured at a part connected to the circular waveguide by: an arc-shaped first wall surface; an arc-shaped second wall surface that faces the first wall surface; the first inclined surface; and the second inclined surface, wherein a distance between the first wall surface and the second wall surface decreases from the circular waveguide side toward the quadrangular waveguide side. ### Claim 12 (depends on 8) The polarization coupler according to claim 8, wherein the connector waveguide is configured at a part connected to the circular waveguide by: an arc-shaped first wall surface that has the same diameter as the inner diameter of the circular waveguide; an arc-shaped second wall surface that faces the first wall surface and has the same diameter as the inner diameter of the circular waveguide; the first inclined surface; and the second inclined surface, wherein a distance between the first wall surface and the second wall surface decreases from the circular waveguide side toward the quadrangular waveguide side. ### Claim 13 (depends on 9) The polarization coupler according to claim 9, wherein the connector waveguide is configured at a part connected to the circular waveguide by: an arc-shaped first wall surface that has the same diameter as the inner diameter of the circular waveguide; an arc-shaped second wall surface that faces the first wall surface and has the same diameter as the inner diameter of the circular waveguide; the first inclined surface; and the second inclined surface, wherein a distance between the first wall surface and the second wall surface decreases from the circular waveguide side toward the quadrangular waveguide side. ### Claim 14 (depends on 8) The polarization coupler according to claim 8, wherein the connector waveguide is configured at a part connected to the circular waveguide by: an arc-shaped first wall surface that has the same diameter as the inner diameter of the circular waveguide; an arc-shaped second wall surface that faces the first wall surface and has the same diameter as the inner diameter of the circular waveguide; the first inclined surface; and the second inclined surface, wherein a distance between the first wall surface and the second wall surface decreases, and also the first wall surface and the second wall surface each have a diameter that increases, from the circular waveguide side toward the quadrangular waveguide side. ### Claim 15 (depends on 9) The polarization coupler according to claim 9, wherein the connector waveguide is configured at a part connected to the circular waveguide by: an arc-shaped first wall surface that has the same diameter as the inner diameter of the circular waveguide; an arc-shaped second wall surface that faces the first wall surface and has the same diameter as the inner diameter of the circular waveguide; the first inclined surface; and the second inclined surface, wherein a distance between the first wall surface and the second wall surface decreases, and also the first wall surface and the second wall surface each have a diameter that increases, from the circular waveguide side toward the quadrangular waveguide side. ### Claim at position 14 16-25. (canceled) ### Claim 26 (depends on 1) The polarization coupler according to claim 1, wherein the conductor wall is formed integrally with the circular waveguide and the quadrangular waveguide. ### Claim 27 (canceled) ### Claim 28 (depends on 1) The polarization coupler according to claim 1, wherein the quadrangular waveguide has a long side longer than the inner diameter of the circular waveguide, and a distance between the first wall surface and the second wall surface of the connector waveguide increases from the circular waveguide side to the quadrangular waveguide. ### Claim 29 (depends on 1) The polarization coupler according to claim 1, wherein the quadrangular waveguide has a long side longer than the inner diameter of the circular waveguide, and at a part where the connector waveguide is connected with the circular waveguide, the first wall surface and the second wall surface each are formed in an arc-shape having the same diameter as the inner diameter of the circular waveguide, and a distance between the first wall surface and the second wall surface increases from the circular waveguide side to the quadrangular waveguide.