摘要 |
<p>A ranging system such as a radar system transmits signal pulses toward a diffuse target, such as an atmospheric disturbance. The echoes are processed by quantizing and by doppler filtering to produce a plurality of frequency components representing the radial velocities of various parts of the disturbance, which components are expected to be contaminated by an unknown amount of noise. The noise value is established by squaring the echo signals to produce power-representative signals. The signal samples are ranked according to amplitude, and one or more of the largest-value samples are discarded to reduce the order of the sample set. A Kolmogorov-Smirnov test statistic is generated and compared with a threshold established by the desired confidence level. If the test statistic exceeds the threshold, the order of the sample set is again reduced, and the test statistic again compared with the threshold. The noise level is deemed to be represented by the current reduced-order set when the test statistic does not exceed the threshold. <IMAGE></p> |