Blood Flow Velocity Measurement: CCF Based on I/Q signal

Blood flow velocity measurement by ultrasonic techniques has proved to be a valuable tool for clinical diagnosis. Cross-correlation technique(CCF) is a classic one among various measurement methods. For most CCF blood flow measurement related papers, RF signal is widely mentioned, without in-phase/quadrature (I/Q) signal. This paper discusses CCF based on I/Q signal instead of traditional RF echoes, for more precise blood flow velocity measurement, we apply several methods to improve it, weighted average method which assigns different weight for different space distance echoes, and absolute distance limiting method which quite improves traditional parabolic-fit interpolation bias problem. Computer simulation and testing demonstrate that our proposed methods have better performance compared with traditional ones.