Approach for ISAR imaging of near-field targets based on coordinate conversion and image interpolation

Inverse synthetic aperture radar(ISAR) imaging of near-field targets is potentially useful in some specific applications, which makes it very important to efficiently produce highquality image of the near-field target. In this paper, the simplified target model with uniform linear motion is applied to the near-field target imaging, which overcomes the complexity of the traditional near-field imaging algorithm. According to this signal model, the method based on coordinate conversion and image interpolation combined with the range-Doppler(R-D) algorithm is proposed to correct the near-field distortion problem. Compared with the back-projection(BP) algorithm, the proposed method produces better focused ISAR images of the near-field target, and decreases the computation complexity significantly.Experimental results of the simulated data have demonstrated the effectiveness and robustness of the proposed method.