| 摘要 |
PURPOSE:To obtain a high-reliability tracking system which is hard to have radio wave disturbance, by tracking a target by using a signal obtained by performing the multiple amplitude modulation of a radio wave from the target through an antenna system. CONSTITUTION:The reflector 2 and feed horn of an antenna system ANT are shifted from a reference axis and rotated at angular frequencies omega1 and omega2. A radio wave from a target is received by ANT and the multiple amplitude modulation of this radio wave is performed; and the resulting wave is demodulated by a demodulator DET and amplfed LFA to be inputted to a BPF1 where a wave having a omega1 is passed, a BPF2 where a wave having a omega2, and a BPF 5 where a wave having a omega1-omega2 is passed. The output of the BPF5 is frequency-demultiplied to generate reference signals R1-R4. The output of the BPF1 and BPF2 are multiplied by the reference signals at an MUT1-MUT4 to detect an azimuth-angle error signal Ez and an elevation-angle error signal EL, which are used to control a servoamplifier SA. A switching circuit SW compares the signals EZ and EL of the omega1 and omega2 systems to apply the signal, which is not disturbed, to the SA, and the ANT is driven so that the error signals are both Os, thereby tracking the target. |
