| 摘要 |
PURPOSE:To widen the opening of antennas, to reduce the effect of a reflected wave and to suppress a phenomenon of a shift increase in maximum frequency, by rotating a fixed antenna and a moving antenna in a prescribed mutual relationship. CONSTITUTION:A fixed antenna 31 and a moving antenna 32 being rotated by a dual rotation mechanism with the antenna 31 as the center of rotation at a large radius, on one hand, and with the circumference of this rotation as the center of rotation at a small radius and at a larger angular speed that of said rotation, on the other, are provided. From the antenna 31 a signal obtained by modulating the amplitude of a carrier wave by a required frequency is emitted, while from the antenna 32 a non-modulated signal is emitted with a frequency different from that of the carrier wave. At a receiving point an amplitude- modulated wave emitted from the antenna 31 and a frequency-modulated wave generated by a Doppler effect of the antenna 32 are received, and an information on bearing is obtained therefrom. |
