A stability condition and steady state errors of an α-β-γ filter for radar tracking

We present the necessary and sufficient condition that an alpha - beta - gamma filter is stable. We also show that there exist two different stable alpha - beta - gamma filters one of which is derived from Kalman filter equations and another from fading memory filter equations. We derive equations of the steady state variances of an alpha - beta - gamma filter for a constant velocity target. We also present that the necessary and sufficient condition that these variances become positive. Furthermore, we present that this condition is equivalent to the stability condition.