Entropy minimization based phase compensation for echoes of high dynamic targets

This paper presents a phase compensation method for high dynamic target echoes, of which the echo phase is not linear but polynomial. Restricted by minimum entropy criterion, coefficients of each order of the echo phase are estimated and utilized to compensate the nonlinearity of the phase. Then the Doppler frequency estimation with higher accuracy can be gained by FFT or other frequency estimation techniques. The experiment result shows that the nonlinearity of the phase is estimated efficiently and the compensated FFT estimation is asymptotically unbiased with low root mean square error (RMSE), which, at the same time, allows integrating more echoes leading to better performances. The entropy minimization based phase compensation (EMPC) technique is potential to adapt to the maneuvering character of the high dynamic targets and improve the velocity estimation accuracy.