The paper analyses and studys the technology of filter and forecast current fire-control system of antiaircraft artillery. A kind of α-β filter was designed. It converted the requirement of frequency-field in series systems and Z-field in discrete systems into the requirement of eigenvalue of response based on typical inspirit. We can integrate the requirement of eigenvalue in time-field

converte the result in Z-field and ascertain the α-β filter. This papershows the transfer-function of the kind α-β filter

analyses the parameters

discusses the static error

and realizes the emluator for the design.