GB720153A - Improvements in or relating to devices for converting plane-polarised electromagnetic energy into elliptically-polarised electromagnetic energy - Google Patents

Abstract

720,153. Wave-guides. GENERAL ELECTRIC CO., Ltd. June 16, 1953 [June 19, 1952], No. 15523/52. Class 40 (8). A wave-guide for converting plane-polarized into elliptically-polarized electromagnetic energy has a longitudinal groove on its inner surface. A circular guide may have diametral grooves 4, 5, and may be coupled to a guide which supplies energy polarized in a plane at 45 degrees to the plane containing the grooves 4, 5. The length of the guide may be such that the relative phase shift of the two components of the energy passing through the guide is 90-degrees, thus producing circularly-polarized energy. Examples of the length and diameter of the guide, and dimensions of the grooves are given. The guide including the grooves may be filled with a dielectric material such as polythene or a strip 13 of dielectric material may lie across the guide and extend the length of the guide. The guide may be electro-formed on a suitable mandrel or machined from a brass tube. The guide may be of square section, the grooves being provided in opposite faces of the guide, and the guide may be excited by a probe lying in a plane perpendicular to the guide axis and inclined at 45 degrees to each pair of adjacent faces. Alternatively, the square guide may be supplied with energy from a rectangular guide through a transition section which rotates the field through 45 degrees.