| 摘要 |
<p>PURPOSE:To obtain a demodulation circuit for a coded CW radar in which the Doppler effect due to a moving target can be measured accurately along with the distance therefrom by suppressing a field through signal and a reflection signal from a clutter sufficiently. CONSTITUTION:Outputs from an A/D converter 14 are fed to N correlators 15. An n-th (2<=n<=N) correlator performs correlation processing with a time lag T/N (T: transmission repetitive period) behind (n-1)th correlator. A first shift register 16-1 delays the input signal by a time T and an n-th shift register delays the input signal by a time equal to 1/N that of an (n-1)th shift register. An (n-1)th subtractor 17 determines the difference of outputs from the (n-1)th and n-th shift registers. An FFT processing section 13 determines the Doppler effect and the distance of a moving target based on the outputs from all substractors.</p> |
