Research On Multi-pulse Ranging Algorithm And Its Application Based On Time-domain Expansion With Vernier Principle

With the development of Optronics and electronics and the advent of varied novel light sources(laser,infrared light, etc) in the modern times, noncontact measurement based on electromagnetic distance measuring technique has acquired rapid development. Compared with artificial measurement, the advantages of electromagnetic distance measuring technique are as follows: simplicity of operation, high accuracy, real-time rapid measurement, safety and adapt to the rugged measuring surrounding. So it has gradually become hot spot of research in worldwide, which promotes further study in the fields of time interval measurement, signal modulation, time discrimination technique and high stability of frequency source.The main work of this thesis is focuses on pulse ranging technology and its application. Firstly, this thesis presents the main ways of electromagnetic distance measurement. By means of comparative analysis, microwave ranging technique has good performance with environmental adaptability and stability, so that it's suitable for level measurement in industry and has good application prospects. Afterwards, we focus on the time interval measuring technique of high precision, and then introduce a novel multi-pulse ranging algorithm based on time-domain expansion with vernier principle. According to level measurement of non-contact and short distance, a microwave pulse modulation ranging algorithm, which is based on time-domain expansion with vernier principle and the method of cross correlation, is proposed. Furthermore, it's also verified by computer simulation. Finally, multi-pulse ranging algorithm based on time-domain expansion with vernier principle is practically applied to measure lengths of network cables.The innovations and the characteristics of this thesis are as follows:(1) Multi-pulse ranging algorithm based on time-domain expanding technique with vernier principle has been presented, the thought of which is based on the tiny difference between the periods of two clocks. The time interval between transmitted pulse and received pulse was interpolatively expanded to improve the accuracy of time measurement, so that distance measurement of high precision can be achieved. Furthermore, the microwave pulse modulation ranging algorithm based on the time-domain expanding technique with vernier and the cross correlation method is proposed, which has been simulated and verified by ADS.(2) As to the time interval measurement technology, frequency stability of clock signal in vernier interpolation method has become an issue of concern, and the theoretical equation to determine the frequency stability of clock signal is obtained with the certain measurement error in time-domain.(3) An equipment to measure length of standard 5- species UTP network cables has been adopted. Pulse electric wave is transfered by twisted-pair, and the multi-pulse ranging algorithm based on time-domain expansion with vernier principle has been used to measure the travel time, and then the distance value is computed by MCU.