The study of recognizing and eliminating fake projectile signals in the sky screen

The sky-screen is an instrument to measure the parameter of flying projectile in the ranger, it is often interfered by the external fake projectile signals that can cause equipments to trigger mistakenly and lead to work abnormally in the measurement system. The character of detection screen thickness is used in the sky-screen to analyze the signal on the projectile and fake projectile when it pass the screen, and calculate the pulse width that the projectile and fake projectile generates. According to the feature of the pulse width, the technology of CPLD was used to recognize projectile signal and eliminate the fake signal, the logic circuit of recognizing and eliminating was designed, the method was applied in the across screen fire measuring system, the result proves the method can identify projectile signal and eliminate the fake signal.