Efficient Acceleration for Total Focusing Method Based on Advanced Parallel Computing in FPGA

Abstract

Total focusing method (TFM) has improved resolution and accuracy over traditional ultrasonic phased array technology. In this paper, an advanced parallel architecture in field programmable gate arrays is suggested to significantly accelerate the imaging efficiency of TFM. Several techniques are investigated, including the real-time concurrent calculation for time of flight, parallel generation of multiple pixels, and the Hilbert transform to the pixels array. This architecture achieves the real-time computation of the flight times for each pixel and the concurrent generation of double pixels for TFM imaging. Compared to conventional methods, the efficiency of TFM imaging is greatly accelerated and the impact from the increase of element and pixel number is also effectively reduced. Simulation data was used to verify the architecture, and experiment results confirmed that the efficiency was only related to the pulse repeated frequency and element number, which reaches to the physical limitation of TFM inspection. This approach also shows that high efficiency is maintained when pixel number increases, and a strict real-time imaging can be achieved in this architecture. As a result, an effective way for the fast inspection with TFM is provided.