测速光幕靶用数字信号处理算法

针对光幕靶在使用中易受到蚊虫、冲击波和光电器件随机噪声干扰因而可靠性差的技术难题，提出一种测速光幕靶用数字信号处理算法。利用数据采集仪采集光幕靶输出的弹丸过靶信号，通过莱达因准则剔除偶发性干扰数据。通过阈值比较法判断出弹丸信号的时间范围后，利用4次高斯公式对一定时间范围内的采样数据进行曲线拟合，并准确计算出半峰值触发时刻点，实现低采样率下的高精度测量。研究的信号处理算法利用计算机进行仿真验证，其原理正确，计算效率高。配合XGK-2002型光幕靶进行实弹射击试验，测试数据表明:该算法可准确计算出各类弹丸信号的过幕时刻，极大地提高了光幕靶的稳定性和适用范围，测量相对误差不大于0.1%。研究的算法同样适用于一类动态特征信号的提取与计算。

Digital signal processing algorithm for velocity measurement optical screen

In order to solve the technical problem of the incorrect signal of optical screen due to disturbance of mosquitoes, impact wave or noise from photoelectric device, a digital signal processing algorithm was put forward. The algorithm used the data acquisition (DAQ) instrument to collect signals of the projectile passing through the screen, and then used 3σ criterion to remove singular points. The triggering moment of the half peak could be selected correctively by means of the 4-power Gaussian curve fitting for the sampling data to achieve high-precision measurement with the lower sampling rate after the time frame of the projectile signal was determined by threshold comparison. The testing results of the computer simulation and the ball firing show that the algorithm is correct with high efficiency. The testing result of the ball firing of the XGK-2002 optical screen shows that the algorithm is eligible to measure the moment when various projectiles crossing through the screen and improves the application field and stability of the light screen target, the measurement relative error of the algorithm is less than 0.1％. The algorithm is also applies for the extraction and calculation of dynamic characteristics of this kind of signals such as sky screen target.