| 摘要 |
<p>PURPOSE: To reduce echo noises in a radar system, especially those having returned from a diffused target like a meteorological phenomenon, by causing a received echo to pass a Doppler filer, squaring its frequency components, and performing the calculation of KolmogorovSmirnov pilot statistics, threshold comparison, and noise calculation. CONSTITUTION: An echo received by transmitting a pulse to a diffused target is processed 210 by quantization and the action of a Doppler filter, and a plurality of frequency components representing the radial-direction speeds of various parts of the target. These components are contaminated by unknown amounts of noises. By squaring 410 the echo signal and generating a signal representing energy, a noise value is set. Signal samples are arranged 412 in order according to the amplitudes, and a sample or more of a largest value are disused 414, and the scale of the set of samples is reduced. A Kolmogorov-Smirnov pilot statistic is generated 418, and is compared 420 with a threshold value. If the pilot statistic exceeds the threshold value, the scale of the set of samples is reduced 414 again, and the pilot statistic is compared 420 with the threshold value again. When the pilot statistic does not exceed the threshold value, the noise level is regarded as being represented by a set of a scale reduced from the present scale.</p> |
