A Multiple-Polarisation Ultra-High Frequency Radiation Source

1,172,006. Producing rotating polarization. COMMISSARIAT A L'ENERGIE ATOMIQUE. 9 May, 1967 [11 May, 1966]. No. 21533/67. Heading H1W. A wave of continuously rotating polarization is produced by means of a bend in a circular waveguide. An H 11 wave propagating in bend 3, Fig. 5 (which extends in a plane perpendicular to the plane of the drawing), may in general be decomposed into two waves having directions of polarization respectively E and H. For the E component, the bend behaves as an E-plane bend and for the H component, as an H-plane bend. The components therefore suffer different phase-shifts and, in general, the result is an elliptically polarized wave at the output. If the bend is such that the phase difference amounts to #/2 and the input wave lies at an angle #/4 to E and H, the result is a circularly polarized wave. The direction of polarization of the incident wave may be varied by adjusting the angular position of a rectangular-to-circular transistion 4 which is joined to the bend 3 by a rotatable joint.