A new algorithm for time-delay estimation in ultrasonic echo signals [Correspondence].

Time-delay estimation determines the relative displacement between two ultrasound echo signals. In this paper, we propose a new time-delay estimation algorithm which uses only the sign function to obtain the corresponding timedelay estimate. The performance of the proposed algorithm was compared with two established algorithms, i.e., normalized cross-correlation (NCC) and sum of squared differences (SSD), using metrics such as statistical analysis and computational time. All simulated ultrasound echo signals were generated using ultrasound simulation software. The results indicated that overall, the proposed algorithm had similar accuracy and precision compared with the NCC and SSD algorithms; however, the computational time of the proposed algorithm was about 70% less than NCC and SSD, which showed a significant improvement. [ABSTRACT FROM AUTHOR]