An Efficient Digital CZT Beamforming Design for Near-Field 3-D Sonar Imaging

摘要: A planar array of sensors is required to collect the signals coming from a 3-D scene generate volumetric underwater acoustic images. The method most frequently used process acquired digital beamforming algorithm. In general, owing high number and beam signals, computational load prohibitive for real-time image generation. literature, frequency-domain technique based on chirp zeta transform (CZT), which efficient computationally advantageous, has been introduced linear arrays working in far field. This paper proposes an extension CZT that specifically devised cope with requirements sonar imaging. particular, processing wideband collected by generated placed both near-field far-field conditions enabled one or two orders magnitude lower than traditional time-domain implementations. To attain this result, Fresnel delay approximation, useful definition steering angles, setting up multiple focal regions are adopted. addition, convenient cubic resolution cells introduced.