A new method of ship and chaff polarization recognition under rain and snow cluster

The Correlation Characteristics of Polarization Backscattering Matrix of Dense Chaff Clouds

“…3, the middle point (where Δn = 0) is the computed cross to co-polar correlation coefficients Although it is assumed that the shape of the chaff cloud is circular symmetrical, it is interesting that the result for cube is not obviously different from that for the circular symmetry shape such as sphere and cylinder. So (17) and (18) holds not only for the dense chaff clouds with circular symmetrical shape. That is, s 11 and s 12 are independent of each other, and s 11 s * 11  equals the sum of 2s 12 s * 12  and s 11 s * 22 .…”

“…Equation (17) shows that s 11 is uncorrelated to s 12 , that is, the cross to co-polar correlation coefficient Gaussian distribution [22], and they are uncorrelated to each other based on the above analysis, therefore they are independent of each other. This conclusion coincides with the experiments of distributed targets mentioned in [24], and it is independent of the length of dipoles.…”

“…Polarization characteristics play an important role in the jamming recognition and suppression in radar electronic warfare [15][16][17][18]. The scattering characteristics of the dense chaff clouds are not always the same as that of the sparse chaff clouds.…”

Anomalous Propagation Echo Classification of Imbalanced Radar Data with Support Vector Machine

“…The nonnegative and nonzero in (8) denote the fact that x does not satisfy (7). Consequently, ∑ =1 can be analyzed as a misclassification result.…”

“…Moreover, the reliability of the forecasting result may change according to the skill level of meteorologists if the prediction system depends on the expert's decision. Therefore, we need further research on the implementation of a system that can automatically distinguish nonprecipitation echoes from radar data Certain representative types of nonprecipitation echoes are as follows: sea clutter [3,4], sun strobe echoes and radial interference echoes [5], chaff echoes [6,7], and anomalous propagation echoes [8][9][10][11][12][13][14][15][16][17][18][19][20][21]. Among them, an anomalous propagation echo is a radar signal generated by an abnormally refracted radar beam due to the temperature and humidity distribution in the atmosphere.…”