Research Of High Precision In Wireless Ranging

As the rapid development of science and technology,information technology widely used in measuring instruments ,and the penetration of mico-computer hadware and software technology,that promoted the automated topographic mapping. Measurement of the distance always has been the focus of research comtents.The current rangefinders,including laser rangefinder,ultrasonic rangefinder,inrared and microwave rangefinder,each have their own advantages and disadvantages. The ranging system, the most important thing is that measurement range and accuracy.Through accessing to a large number of documents and data, completed the following tasks:First, the principle of pulse-type ranging and phase-type ranging principle are introduced in this paper, and the two distance-measurement methods are compared.It proposed the application of the system ranging method :phase frequency shift ranging method. This method is that through counting to the phase change of the sweep signal to achieve the distance, the accuracy of range and the tested frequency are independent, it is related to the change value of the frequency. Compared with the traditional distance methods, it has high precision and large-scale features.Second, the design of block diagram of the subject ranging system and each module of system are completed in this paper, and using Matlab / Simulink simulation software to simulated each module and achieve that the phase error is about 1.5°,and that the theoretical feasibility of the method can be proved. According to the error analysis of the simulation results. The various types of error is analysised and taked correlation ways in order that error is reduced and the ranging accuracy is improved.In addition to the overall system hardware design and planning, for example, sweep signal source, mixer, filter and other parts of the enlarged crossover design, and focused on the design of a sweep signal source, and carried out relevant studies. Using the chip Cyclone IV EP4CGX30CF19C7N of Altera companies to design the divider and completed QUARTUSⅡfunctional of frequency divider.Finally, based on the issues proposed the next steps and performance improvements. Such as improving the phase measurement methods, improved data processing algorithms and so on. Precision ranging system has broad development space, it can be used in many important areas, However, due to short time of this research project, system performance remains to be improved, especially in the signal phase frequency detector, phase locked filtering need to be further improved.