APPROACH OF IMPROVING PRECISION IN ULTRASONIC DOPPLER BLOODSTREAM SPEED MEASUREMENT BY CHAOS-BASED FREQUENCY DETECTING  

作　　者：Zhang Shuqing Jin Shijiu Lv Jiangtao Zhang Liguo Li Jun 

机构地区：[1]Electrical Engineering Institute, Yanshan University, Qinhuangdao 066004, China [2]Precision Instrument and Photoelectric Engineering Institute, Tianjin University, Tianjin 300072, China

出　　处：《Journal of Electronics(China)》2006年第3期457-460,共4页电子科学学刊（英文版）

基　　金：Supported by the National Natural Science Foundation of China (No.60102002)the Huoyingdong Education Foundation (No.81057)the Doctoral Foundation of Hebei Province of China(No.B2004522).

摘　　要：It is critical for cerebral vascular disease diagnosis through Doppler to detect the maximum and the minimum of the carotid blood flow speed accurately. A kind of Duffing system under an external periodic power with dump is introduced in the letter, numerical analysis is carried out by four-order Runge-Kutta method. An oscillator array is designed according to the frequency of the ultrasonic wave. When the external signals are inputted, computational algorithm is used to scan the array in turn and analyze the result, and the frequency can be determined. Based on the methods above, detecting the carotid blood flow speed accurately is realized. The Signal-to-Noise Ratio (SNR) of-20.23dB is obtained by the result of experiments. In conclusion, the SNR has been improved and the precision of the measured bloodstream speed has been increased, which can be 0.069% to 0.13%.It is critical for cerebral vascular disease diagnosis through Doppler to detect the maximum and the minimum of the carotid blood flow speed accurately. A kind of Duffing system under an external periodic power with dump is introduced in the letter, numerical analysis is carried out by four-order Runge-Kutta method. An oscillator array is designed according to the frequency of the ultrasonic wave. When the external signals are inputted, computational algorithm is used to scan the array in turn and analyze the result, and the frequency can be determined. Based on the methods above, detecting the carotid blood flow speed accurately is realized. The Signal-to-Noise Ratio （SNR） of-20.23dB is obtained by the result of experiments. In conclusion, the SNR has been improved and the precision of the measured bloodstream speed has been increased, which can be 0.069% to 0.13%.

关 键 词：CHAOS Frequency detecting Bloodstream speed measuring Ultrasonic Doppler Signal-to-Noise Ratio （SNR） Measuring precision 

分 类 号：TH77[机械工程—仪器科学与技术]