Optional Optimization Algorithms for Time-of-Flight System

Self-interference driving technique is one of the most important methods for the highly accurate time-of-flight (TOF) measurement, which was first proposed in 1992. However, since this method is susceptible to noise, its industrialization is still a matter open for debate up to now. To address this problem, this paper presents an optimized ultrasound-driven method of incorporation of the amplitude modulation and phase modulation of the transmit-receive technique. Moreover, this paper proposes two optional algorithms to achieve TOF calculations according to different signal-to-noise ratio situations named the zero-crossing tracking and time-shifted superposition methods. The entire testing process is integrated in a digital-signal-processing-based ultrasonic measuring system. After validation with an ultrasonic ranging experimental platform, the results indicate that a feasible system is provided with the advantages of high noise immunity, accuracy, reliability, and ease of implementation.