Space target velocity compensation based on fractional autocorrelation and PSO optimization

Distortion compensation of High-resolution range profile plays an important role in ISAR imaging of high-speed space target. Since the baseband echo of such target is a multi-component linear frequency modulated(LFM) signal with identical chirp rates. Since the peaks of its ambiguity function lie on a set of parallel lines, whose slope is relative to the chirp rate, an estimator based on the fractional autocorrelation is provided to estimate the target's radial velocity. Furthermore, the particle swarm optimization(PSO) algorithm is also applied to speed up the progress of parameter estimation,. Finally, the velocity compensation is accomplished with the estimated velocity. Simulations show that the proposed method can compensate the range profile distortion of space target effectively.