In gun bore and recovery through special signal processing of speed missing segments, it is affected by smoke, flame and shock wave and other factors of interference, the interference leads that getting the actual moving target in muzzle moments of the doppler signal energy is particularly weak, speed corresponding losses, it reduces the accuracy of the measurement. According to the interference, using the method based on particle filter (PF) of the trajectory and the velocity compensation, avoids speed missing segments sampling interpolation of velocity curve, and the interpolation of missing segments of speed of fitting method missing interval velocity model is obtained, and then it uses this model to speed recovery optimization. Because the velocity loss section usually appears in the moving target, the muzzle velocity is the key factor to determine the muzzle velocity. Therefore, it is very important for the recovery of the velocity loss.