Modelling of continuously distributed target for bistatic synthetic aperture radar imaging

The point target model is widely used in the synthetic aperture radar (SAR) imaging simulation. Based on this model, the radar echo of a continuously distributed target can be expressed as the linear summation of the echo of many point targets which are known as scatters. However, the discretisation strategy is problematic. The discretisation grid must be very fine to assure convergence, thus the computation burden is heavy. Moreover, the result depends on how the target is discretised. It is shown that the SAR image generated from this model of the same target is inconsistent when using different sampling strategy. To overcome these drawbacks, a parameterised model is proposed in this study, which not only greatly reduce the amount of calculation, but also guarantee consistency of the results. Finally, the correctness of the proposed model is verified by SAR imaging results from the generated echo data.