Microwave High-Speed Continuous Phase Shifter

A continuous phase shifter using circularly polarized helices in a circular waveguide is described. The phase shifter is smaller than previous types and has an insertion loss of less than 0.2 db. Equations for the phase-shift error and the amount of amplitude modulation produced due to reflections and elliptical polarization are derived. Errors less than ±2° can be obtained over a 3 per cent frequency band. A 9,400-mc model designed to rotate at 3,600 rpm is 5¿ inches long and 1 inch in diameter, excluding the motor drive.