CNN-based multiple-input multiple-output radar image enhancement method

In this study, the convolutional neural network (CNN) is utilised to enhance the quality of radar images. First, a fourlayer convolutional neural network is trained. The input of it is a complex valued two-dimensional low-resolution radar image, and the output is the radar-cross-section distribution image. After processed by the proposed network, the sidelobe and grating lobe in the radar image are suppressed, the main lobe of the target is sharpened. Comparing to the commonly used coherence factor method, the proposed method can enhance the image while maintaining the amplitude scaling relation between targets. The feasibility of the proposed method is testified by both simulated and experimental results.