| 摘要 |
In order to compensate the unwanted echo caused by the movement of a moving radar device, an arrangement is provided between the output of a coherent oscillator and the input of a phase discriminator. This arrangement comprises a signal processing stage containing two series-connected phase regulating circuits, namely phase-locked loops. The output signal of the first phase-locked loop displays a mixed frequency which is formed by the sum of the frequency of the output signal of a signal generator and a displacement frequency modulated by the Doppler frequency of the unwanted echo caused by the movement of the radar device. In the second phase-locked loop the output signal of the first phase-locked loop is mixed with a further signal containing the displacement frequency. |
