The motion compensation for ISAR imaging using scattering centroid (called reference centroid method) is proposed and studied. The internal relations and differences between correlation method and the new method are analyzed. The noise effect on the motion compensation is discussed. To solve the problem, a new method' which uses echo goodness-of-fit curve to smooth the centroid range trace and phase trace is proposed. The reference centroid method is used to process the simulative and real ISAR data of movi...