Fig. 10

Radar echo power aspect ratio (dB) defined as \(\log 10\left( {P_{v} } \right) - \left( {\log 10\left( {P_{N} } \right) + \log 10\left( {P_{E} } \right)} \right)/2\) calculated in the same way as \(\sigma^{2}\) (“Theoretical bases and practical methods of \(\varepsilon\) estimation” section) versus \(\log 10\left( {\varepsilon_{R} } \right)\) (black dots) and \(\log 10\left( {\varepsilon_{U} } \right)\) (red dots). The statistics was made on the ShUREX2016 flights. The blue dashed line (1) shows the minimum \(\varepsilon\) values detectable by the radar. The blue dotted dashed line shows the level equal to 10 times the minimum threshold