Range super resolution for near-field coherent imaging

The design of beamformer is a critical component in the development of coherent imaging. Conventional delay-and-sum beamformer is intuitive and easy to implement, however it does not provide good range resolution for narrow-band waveforms. In this paper, we propose a technique that optimizes the reconstruction kernel to approximate an ideal impulse, and has control over mainlobe/sidelobe tradeoff. Preliminary simulation has demonstrated that the new method achieves significantly better range resolution than simple delay-and-sum beamformers for narrow and medium band near-field imaging.