JPS567067A - Detector for angle error - Google Patents

Abstract

PURPOSE:To keep a signal received in good condition at all times and thus to generate a stable error voltage by a method wherein a polarization converter is controlled against a polarization arriving arbitrarily from a target, and an influence on angle error involved thereby is eliminated. CONSTITUTION:A signal from a target is received on a primary radiator 1, processed through polarization converters 4, 5 of 90- and 180-degree phase difference plates, and a main polarization, crossed polarization components Exc, Eyc are extracted from a polarized wave separator 6. The component Eyc is detected by a phase detector (PSD) 17 with an output of a voltage control oscillator 90 degrees different in phase with the component Exc, and from driving the converter 4 through a motor 19 so as to zero the output, a condition alpha=gamma is satisfied and an expression I is converted into an expression II. From driving the converter 5 similarly, a condition III is satisfied and the component Exc becomes a value to satisfy an expression IV, thus obtaining a full power of fundamental mode component. A signal is received in good condition at all times and a stable error voltage is generated by removing an influence of an angle error signal according to this control with a coordinate converter 59. alpha, beta: angles of the converters 4, 5; gamma: angle between maximum polarization pressure Emax and axis of coordinates.