procedure and apparatus for the measurement of muzzle velocity projectiles by doppler radar

摘要

A muzzle velocity chronograph method and apparatus is described for measuring the velocity of a projectile (11) from a gun (13). In this method and apparatus a conventional radar Doppler signal from a radar device (15) is sampled and digitized by an analog-to-digital converter (23) and arranged in a succession of groups, each group representing a separate time period. A fast-Fourier transform is them computed for each group of samples by a signal processor (27) and peaks frequency measurements in the transformed data are tracked from one time period to the next. These peaks indicate the velocities of the projectile of interest and any other nearby moving objects. Finally, a least mean square error curve fit and standard regression algorithm are used to deduce the projectile's initial, muzzle velocity and the results displayed on a display (31). The method and apparatus provides accurate muzzle velocity determinaltions even in circumstances where the Doppler signal contains substantial interference caused, for example, by random noise and the presence of moving fragments in the direction of the projectile.