BEAM CONTROLLER

PURPOSE:To improve the prediction accuracy of a future position at low cost by predicting an aimed beam direction from the target and acceleration of a target being tracked and the curvature of the target. CONSTITUTION:A radar 1 transforms the position vector of the target into components of orthogonal coordinates and outputs them. A speed calculating device 2 differentiates the position vector with time to calculate a speed vector on the orthogonal coordinates. A curvature calculating device 4 further differentiates the speed vector calculated by the device 2 with time to calculate an acceleration vector. The curvature calculating device 4 calculates the curvature from the position, speed, and acceleration calculated by the respective devices. A sampling interval calculating device 5 stores a necessary sampling interval previously and outputs its information. Thus, a predicted position calculating device 6 calculates a future target position vector. Then, a coordinate transformer 7 finds a next beam direction from an inputted future target position vector and calculates its elevation angle and azimuth angle. A phase shift controller 8 controls the quantity of phase shifting of a phase shifter 9 according to the found beam direction.