| 摘要 |
PURPOSE:To operate correct detection even when the velocity of a target exceeds the maximum Doppler measurement velocity by eliminating the echo velocity phenomenon inherent to the pulse Doppler radar system, and measuring the true velocity distribution of the distributed target. CONSTITUTION:Transmitter 9 uses two different repetition frequencies by switching them and sends microwave pulses, and the reflected waves are A-D converted by converters 6a and 6b, via mixer 3 and phase detector 5. Next, positive and negative Doppler average velocities are obtained from the frequency spectrum calculated by the high-speed Fourier transformation operated by average velocity processing circuits 10a, 10b, and the amplitude of the reflected signal from the target is taken out. Further, the echo effect is eliminated by echo velocity compensation circuit 11, and the absolute value of the velocity distribution is determined by Doppler true velocity distribution forming circuit 12 and is displayed in display circuit 13. For this reason, the Doppler velocity echo effect can be eliminated and the true velocity distribution can be reproduced. |
