Motion compensation of non-linear stepped-frequency pulse train by least step error

Traditional stepped-frequency chirp pulse train suffers from high sidelobes and difficulty in compensating Doppler effect caused by target motion. This paper investigates a class of non-linear stepped-frequency chirp pulse train with low sidelobes and capability of clutter cancelation and motion compensation. An easy realizable least step error algorithm is developed to estimate the target's radial velocity, which avoids multiple bursts required by other methods. The high signal-to-noise ratio as a result of sub-pulse compression assures the accuracy of estimation. The Cramer-Rao bound for lower limit on velocity estimation of the pulse train is derived to demonstrate its performance.