A new approach for estimation and compensation of target translational motion in ISAR imaging

Abstract

A noveltechnique/or estimation andcompemation ifradar targettramiatiol101motion ispresented lis theoretical derivation and its application to real radar data /or different clarses iftargets (Sh¢J; aircrq/ls) are discussed The proposedalgorithm is baredon a closed-loopprocessing choin, thotprocesses groups ifreceivedpulses carrying out a./fequency-domoin al1O{ysis to estimate the target unknown relative motion, andthen uses the estimatedrange-rate to compematepu/se-to-pu/se range shi/i. The simplicig; and robustness if the proposed approach maM it e.special{y suitable/or real-time applicatiol1J; andit can be the basis or the initial step ifmany different radar imagingprocessingstrategies.Many proposed methods (see [2] to [5]) based on minimisation/maximisation of cost/score functions like amplitude correlation, entropy minimisation, contrast optimisation, etc, often lead to unreliable estimation of radar to target rangerate and/or may require long observation time and data storing before a reliable motion estimation can be achieved. Key features of proposed method is to achieve instantaneous and very accurate estimation of relative range-rate by a simple and a computationally affordable processing suitable for reliable real time ISAR imaging applications.The paper is organized as follows: in §2 we illustrate the theoretical derivation of the proposed algorithm, while in §3 we show its results on simulated data. Finally, in §4 we discuss the results of the proposed algorithm on real data, and in §5 we draw our conclusions.

Method for inverse synthetic aperture radar imaging of space debris using improved genetic algorithm

“…Secondly, the target spinning frequency remains constant in the imaging interval. Also we assume that the translation motion has been compensated completely and only consider the echo‐modulation caused by the spinning motion [10–12]. As shown in Fig.…”

Precise Radial Velocity Estimation for Inverse Synthetic Aperture Radar

“…Thus the ISAR system is usually accompanied by a narrowband mode or narrowband radar, which conducts the functions of searching and tracking the target but rarely provides precision high enough for the target velocity while inducing implementation difficulties in the radar system. An alternative solution is to estimate velocity directly from the wideband echo by signal processing, which has the advantage of decreasing the burden of the radar system, and this work has attracted much attention in the radar community [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21].…”

“…An efficient algorithm for maximum likelihood estimation of translational motion was described in [20]; however, it assumed that the maximum relative translational motion from pulse to pulse was less than one wavelength. A basic, simple and reliable approach for estimation and compensation of the target relative translational motion was proposed in [21], but the correct behaviour of the algorithm depended on its correct initialisation.…”