| 摘要 |
PURPOSE:To smoothly direct a parabola antenna to the transmitting side and to reduce the automatic tracking time by sensing the difference in level between a main reception level and a sub-reception level and adjusting the azimuth angle of the antenna so that the polarity corresponding to the difference is directed to the opposite polarity side and the reception level is higher than the prescribed value. CONSTITUTION:As to the output signals of main and sub primary radiators 4, 6 disposed at the focal position of a parabola reflecting mirror 2 and at a slightly offset position, main and sub reception level signals are inputted to an input adjustment circuit 30 through BS converters 8, 10 and BS tuners 12, 14. The output from a potentiometer 24 for sensing the angle of elevation and the azimuth angle of the reflective mirror 2 provided to hydraulic actuators 16, 18 and the output of a tilt sensor 28 for sensing the tilt of the ship are also supplied to the circuit 30. These signals are supplied through an A/D converter 32 to the CPU 34. The CPU 34 computes the angle of elevation and the azimuth angle of the mirror 2, sends control signals to solenoid valves 20, 22 and controls the mirror 2 so that the difference between the main and sub reception levels is directed to the opposite polarity and the reception level is larger than the preset value. |
