ISAR Imaging Using a New Stepped-Frequency Signal Format

In stepped-frequency (SF) radar systems, the high-order phase error due to target motion in each burst can blur the range profile seriously. The methods based on motion parameter estimation perform well in most cases. However, the motion parameter estimation is time consuming, which challenges the real-time imaging of a radar target. To solve this problem, a new easy-to-implement variant of SF signal format is proposed in this paper. By employing the new signal, the high-order phase error can be simply eliminated, and the motion parameter estimation is unnecessary, which makes the imaging efficient. The effectiveness of the proposed method is illustrated and analyzed with both simulations and real data.