| 摘要 |
Apparatus for detecting the passing of a projectile and for obtaining information as to at least one of, the velocity of the projectile Vo, the distance of closest approach of the projectile Lo, the time of closest approach of the projectile To, or other information relating to the movement of the projectile, comprises at least one radar device 2 arranged to provide a curtain of radiation across the intended direction of movement of the projectile, each device including means responsive to reflection of radar signals off the projectile to generate a detection signal representative of the doppler shift of the reflected radar signal as a function of time, said detection signal varying in frequency as the projectile passes through the radar curtain, there being a processing means for processing said doppler shifted signal to provide the desired information. There are at least two such apparatus spaced across the trajectory of the projectile, such that, by processing the desired information it is possible as by triangulating to pin point the position of passing of the projectile relative to a datum. <IMAGE> |
