An analogue polarization follower for measuring the Faraday rotation of satellite signals

Conventional methods for measuring polarization angles, as they are employed in measuring the Faraday rotation of satellite signals, determine the time elapsed between two zeros of the polarization fading. The instrumentation described in this paper, however, makes continuous measurement and recording possible by application of a fast electronic scanning and orientation method to the steerable polarization pattern of a crossed-dipole antenna. The information obtained by the intersection of the incident polarization and the pattern scan controls a servo system that in turn steers the system pattern in order to follow the incident polarization angle. System function, theory of operation, and test recordings that are obtained from v.h.f. satellite signals are presented and discussed.