GB882029A - Waveguide rotating joint - Google Patents

Abstract

882,029. Waveguide switches. COMPAGNIE FRANCAISE THOMSON-HOUSTON. Aug. 17, 1959 [Aug. 19, 1958], No. 28072/59. Class 40(8). A waveguide rotating joint arrangement comprises two coaxial circular waveguide sections 1, 2 rotatable at 9 relatively to each other about their common axis, two separate waveguides 5, 6 and 7, 8 coupled to each section 1, 2, respectively, and having their longitudinal axes perpendicular to each other and to the axis of the circular waveguide section, and a vane 12, 13 positioned in an axial plane of each of the sections 1, 2 and orientated at an angle of 45 degrees to the longitudinal axes of the waveguides 5, 6 and 7, 8 coupled thereto, whereby coupling is provided between one of the waveguides 5, 6 and one of the waveguides 7, 8 and between the other of the waveguides 5, 6 and the other of the waveguides 7, 8. The waveguides 5, 6, 7 and 8 can be rectangular in cross-section with their major transverse axes parallel to the axis of the. waveguide section 1, 2, or can comprise coaxial lines. The longitudinal axes of the guides 5 and 6 are relatively displaced along the axis of the guide 1 by approximately half a wavelength in the guide of the midpoint of the pass-band that the arrangement is designed to transmit, and the guide section 1 is terminated by a piston 10 at approximately a quarter wavelength from the longitudinal axis of the nearest guide 5 or by a piston comprising several coaxial cylindrical elements of decreasing diameter as described in Specification 870,873. The guides 7, 8 and the piston 11 are similarly arranged. The vanes 12 and 13 are of length equal to one or an odd number of quarter wavelengths. In the arrangement shown each vane 12, 13 lies in a plane which bisects the angle between the guides 5, 6 and 7, 8 respectively, the guide 5 being coupled to the guide 8 and the guide 6 being coupled to the guide 7. The guide 5 can be coupled to the guide 7 and the guide 6 to the guide 8 by rotating one of the vanes through- 90 degrees. The arrangement can be used for the separate supply of two rotating antenna of a radar detection system. If vanes 12 and 13 are supported by a low loss insulator the arrangement functions in the X-band for applied powers greater than 200 kw peak value in each of the channels. In the case of the S-band peak powers higher than 1 mw can be applied.