The Amplitude Statistics of Aircraft Radar Echoes

Recorded CW radar echoes from a number of aircraft have been analyzed to determine the characteristics of the amplitude fluctuations and the extent to which these vary among different aircraft. The statistics of the echoes from four targets (two jets and two piston aircraft) were found to exhibit marked similarities; typically, the echo power was exponentially distributed, with a correlation time on the order of 0.05 s. Families of probability-distribution functions were derived which show how the amplitude statistics are affected by integration.