| Ultrasonic phased array inspection is an important branch of nondestructive testing,its main feature is flexibly control of beam synthesis,emission and deflection focusing,to realize the scanning of complex shape objects.The speed and accuracy of data processing are the main factors that affect the detection efficiency and imaging quality of UPA.Therefore,it is significant to adopt appropriate algorithms to improve the detection performance of phased array.Coordinate rotation digital computing method can realize various complex function operations by simple addition and shift operations,which is suitable for high speed digital circuit implementation.So this paper is titled“the research and application of the key technologies of ultrasonic phased array instrument based on improved CORDIC algorithm”,proposed the technologies of ultrasonic phased array focusing rule parameters real-time calculation and ultrasonic S scanning imaging,providing a new idea for the data processing methods of ultrasonic phased array,which has important academic value and practical significance for the development of ultrasonic phased array testing technology.This paper focuses on the application of improved CORDIC algorithm in ultrasonic phased array inspection,main works include:?1?The principle of CORDIC algorithm and improved algorithms,focusing on the high radix CORDIC algorithm,scale free factor CORDIC algorithm,angle recoding CORDIC algorithm,and their characteristics and application analysis;?2?Based on the high radix CORDIC algorithm,an ultrasonic phased array focusing law calculator?Solving sin and cos functions?is designed,and the mathematical model of the focusing law and time delay calculator is set up.The time for the central array element reaches the focal point F is derived,and the delay solution method is constructed based on the focusing rule of the interval compression equation,and the implementation scheme of the transmitting and receiving delay system is established.The experimental results show that when the CORDIC iteration number is n,the absolute error produced by value of sin and cos functions can be less than 10-?n-1?.?3?The S scanning technology based on high radix CORDIC algorithm for ultrasonic phased array is studied.The coordinate transformation of ultrasonic echo signal is realized by using the basic radix-4 CORDIC algorithm,and the real-time performance of ultrasonic phased array image reconstruction is improved.The experimental results show that the coordinate conversion absolute error of CORDIC algorithm can be less than 1.5×10-3,and the coordinate conversion speed is about 5 times higher than the traditional method,which greatly improves the speed of S scanning. |
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