Weighted Filtering of Monopulse Signals

The long tailed distribution of the angular noise (Glint) of complex radar targets implies that simple averaging/filtering of monopulse measurements is not effective. Glint noise is one of the greatest contributions to the miss distance of missiles with radar seekers. The weighted average of the monopulse measurements drastically improve the estimation of the Line of Sight angle lambda. In this paper we generalize the weighted average to estimate also the LoS rate. and second derivative lambda. (lambda) over dot and (lambda) over dot are necessary for the homing phase of a missile with a radar seeker. The present algorithm simplifies the implementation and improves the performance of the Proportional Navigation (PN) and the Augmented Proportional Navigation (APN) laws. The weighted average algorithm is recursively calculated and has a single parameter which governs the exponentialy decaying filter memory.