Suppression of log-Weibull Distributed Ground Clutter Observed by L-band Radar

Abstract

Ground clutter of cultivated land was measured using an L-band long-range air-route surveillance radar (ARSR). The observed area was on the Ohsumi peninsula across the big bay of Kagoshima, a distance from the radar site of 23.3km over the sea. Weather conditions were clear and the wind velocity was 3.7 to 18.5m/s. To determine the ground clutter amplitude statistics, we introduced the Akaike Information Criterion (AIC), which is more rigorous fit of the distribution to the data than the least squares method. It was discovered that ground clutter obeys the Weibull, log-Weibull and K-distributions. To suppress such ground clutter, a CFAR circuit normalized by the standard deviation was proposed. It was analytically shown that this circuit is valid for the Weibull distribution. On the other hand, the simulation was carried out for the log-Weibull and K-distributions, since, it is not possible to show analytically that this circuit validates for these distributions.