ISAR echoes coherent processing and imaging using PSO-based adaptive joint time-frequency method

In most cases, the ISAR raw data is usually not coherent because it is difficult to tracking the target center precisely. The non-coherent echoes would make the reconstruction of focused ISAR images difficult. In this paper, a Particle Swarm Optimization (PSO) based adaptive joint time-frequency (AJTF) method is proposed for ISAR echoes coherent processing and imaging. The method can estimate the compensated phase precisely without heavy computational burden. Simulated and measured real data show that the method can significantly improve the distorted ISAR image and be suitable for real-time imaging.