Research On Ultrasonic Phased Array Signal Processing Technology Based On CORDIC Algorithm

Ultrasonic phased array?UPA?is the significant method in ultrasonic testing,the central processor unit based on serial processing or traditional digital signal processing technology is difficult to meet the requirement of real-time processing of massive data.T his work try to computing the transcendental functions on the hardware level based on Coordinated Rotation Digital Computer?CORDIC?,to optimize the computing of key functions or data processing algorithms in ultrasonic phased array instrument,ti tled”Research on Ultrasonic Phased Array Signal Processing T echnology Based on CORDIC Algorithm”,study on the ultrasonic echo quadrature demodulation technology,dynamic filtering technology and time gain control technology,which has important academic value and practical significance to reduce the hardware complexity of ultrasonic phased array instrument system and promote the development of NDT technology.the research work was supported by the project of nationa l major instrument development?2013YQ230575?.This paper studies the ultrasonic phased array signal processing techn ology based on CORDIC algorithm,to have a r eview of research progress at home and abroad from both the principle of CORDIC algorithm and its applications in u ltrasonic phased arra y.The main work of this paper includes:?1?Research on the improved SF CORDIC algorithm,applied in the design of the local oscillator generator of quadrature demodulation,and realized on FPGA.Simulation result shows that the improved SF CORDIC algorithm can reduce 29%consumption of the full adders and the 61%consumption of the registers.Registers,the peak relative error of ultrasonic phased array quadrature demodulation module based on SF CORDIC algorithm is less than 0.37%.?2?Proposed the dynami c calculation of filter coefficient based on radix-4CORDIC algorithm,study the architecture of its FPGA implementation and simulation.T he result shows the absolute error of filter coefficient generation system based on CORDIC is less than-2.94×10^-3,the stopband attenuation of the digital filter module based on distributed algorithm is more than-50d B.?3?Using the exponential CORDIC algorithm to convert the ultrasonic d B gain curve into the actual magnification,devise the d B-Magnification calculator based on CORDIC algorithm,study the FPGA implementation of time gain control module of CORDIC algorithm.Simulation result shows that the average relative error of exponential CORDIC on FPGA is less than 0.1%,the maximum relative error of the ultrasonic echo actual gain is less than 0.014%.?4?Setting up an experimental platform for ultrasonic phased array instrument based on FPGA,test functions for quadrature demodulation,dynamic filtering,and time gain control of ultrasonic phased array based on CORDIC algorithm FPGA module,devise integrated application experiment of ultrasonic signal processing based on CORDIC algorithm,S-scanning for T-weld pipe with equal diameter of gasifier tube to verify the effectiveness and practicability of the ultrasonic signal processing technology based on CORDIC algorithm on ultrasonic phased array instrument.