Adaptive Sparse Representation Beamformer for High-Frame-Rate Ultrasound Imaging Instrument

To overcome the disadvantages of low signal-to-noise ratio (SNR) and poor resolution and maintain the high frame rate in plane wave (PW) emission, a novel adaptive sparse representation beamformer (SRBF) for PW emission is proposed. Signal sparse representation with an overcomplete basis can accurately distinguish correlated or even coherent broadband signals coming from different positions in a single realization of data. Therefore, beamspace weighting beamforming based on sparse representation can enhance the on-axis signals while suppressing the interference from the off-axis ones thoroughly and improve the resolution and SNR of PW emission ultrasonic imaging system. Several simulations to evaluate the proposed algorithm in terms of parameter selection, resolution and contrast enhancement, robustness to additive noise, and selection of the lateral range of dictionary are performed. The results show that the proposed method is robust to additive noise, and both higher resolution and contrast are attainable with SRBF in PW emission by comparing with conventional delay and sum, minimum variance beamformer, and phase coherence factor.